Polyimide resin and resin composition, adhesive solution, film-state joining component,and adhesive laminate film improved in moisture resistance using it, and production methods therefor

ABSTRACT

The present invention provides a polyimide resin, a resin composition, an adhesive solution, a film-state joining component, and an adhesive laminate film soluble in a solvent having excellent heat resistance and adhesion, capable of bonding and curing at relatively low temperatures. Specifically, the present invention provides a novel polyimide resin having low water absorption obtained by a reaction between tetracarboxylic acid dianhydride containing ester-acid dianhydride represented by the general formula (1):                    
     wherein X represents —(CH 2 ) k —, or is a divalent group which comprises an aromatic ring, and k is an integer from 1 to 10; and aromatic diamine, where the resin composition and the film-state joining component which comprise a thermosetting resin with excellent adhesion using this resin are preferably used for flexible printed circuit boards, tapes for TAB (Tape Automated Bonding), composite lead frames, and lamination materials, or the like, and an adhesive laminate film suitable for coating of a superconductive wire rod.

RELATED APPLICATIONS

This application is related to, and claims priority from the followinginternational applications: PCT Application No. PCT/JP00/02181designating the United States, filed Apr. 4, 2001, and Japan Application11/102066, filed Apr. 9, 1999; Japan Application 11/113796, filed Apr.21, 1999; Japan Application 11/114191, filed Apr. 21, 1999; JapanApplication 11/114224, filed Apr. 21, 1999; Japan Application 11/316034,filed Nov. 5, 1999; Japan Application 11/316035, filed Nov. 5, 1999;Japan Application 2000/45542, filed Feb. 23, 2000.

TECHNICAL FIELD

The present invention relates to a novel polyimide resin and a resincomposition, an adhesive solution, a film-state joining component, andan adhesive laminate film which comprise the polyimide resin and toproduction methods therefor. The present invention is useful as amaterial for an adhesive having excellent heat resistance and adhesion,which is used for a flexible printed circuit board, a tape for TAB (TapeAutomated Bonding), a composite lead frame, and a lamination material,or the like. Further, it relates to a laminate film suitable for a wirerod coating for superconductivity.

BACKGROUND ART

Recently, downsizing and weight reduction of electronic parts has beendemanded, as electronic devices have been more and more efficient,highly functional, and downsized. Therefore, packaging methods ofsemiconductor elements as well as higher density, higher efficiency, andhigher function of wiring materials or parts for packaging have alsobeen demanded. Especially, there has been a demand for materials showingexcellent adhesion which may be preferably used as high-densitypackaging materials, such as semiconductor packages, COL (Chip on Lead)packages, LOC (Lead on Chip) packages, and MCM (Multi Chip Module) orthe like, and printed-wiring board materials such as multiplayer FPC(Flexible Printed Circuit) as well as aerospace materials.

Conventionally, adhesives such as acrylic adhesives, phenol-typeadhesives, epoxy-type adhesives, and polyimide-type adhesives or thelike are known for their superior mechanical characteristics, heatresistance, and insulating properties in semiconductor packages andother packaging materials.

Phenol-type and epoxy-type adhesives with excellent adhesion are,however, poor in flexibility. There was a problem that acrylic adhesiveshaving excellent flexibility are poor in heat resistance.

In order to solve the aforesaid problems, polyimide is to be used. Amonga variety of organic polymers, polyimide is in widespread application ofthe aerospace field to the electronic communications field and is alsoused as an adhesive because of its excellent heat resistance. However, ahigh temperature around 300° C. and high pressure are required forbonding of a polyimide adhesive having excellent heat resistance, whoseadhesive strength is not such high. Further, since a conventionalpolyimide adhesive has high water absorption and contains many residualvolatile components (the absorbed moisture and the solvent used forproducing an adhesive), for example, a problem such as swelling haseasily arisen when a lead frame using this polyimide adhesive isdip-soldered.

Furthermore, polyimide is soluble only in a few kinds of solvents, suchas N,N-dimethylformaide, DMAc, and NMP (N-methylpyrrolidone) or the likebecause of its very poor solubility in organic solvents. In addition, ithas revealed that these high-boiling solvents are not fully removableeven after drying of the adhesive solution applied onto a film,therefore, the residual solvent content in the film leads to a cause offoaming.

On the other hand, recent development of elementary particle physics hasaccelerated to build particle accelerators which generate further highenergy. For the high energy to be generated, an electromagnet, which cangenerate high magnetic fields by the passage of a large current, isneeded. The use of superconductive magnets with superconductive wirerods have been increased. An oxide having copper as the main constituentis often used as a material for a superconductive wire rod.Characteristics of the electromagnet may be deteriorated by variationsin the oxidization condition of the superconductive wire rod by heatingwhen a thermosetting adhesive is used to coat a superconductive wire rodwith an insulating coating material. It is, therefore, essential forsuch application to use an adhesive which can be cured and bonded at lowtemperatures.

Further, accelerators are devices which accelerate elementary particles,such as protons and electrons, and make protons and protons, andelectrons and electrons to decay by colliding them each other andexamine particles emitted from the decay, wherein a great amount ofradiation is generated considering from the nature of the devices.Accordingly, superior radiation resistance is required for insulatingcoating materials and adhesives.

In the application for these superconductive magnets, particularly inthe coating of wire rods for superconductivity used at an extremely lowtemperature, laminates made by depositing thermosetting resins havingepoxy resin as the main agent on polyimide films have been used so far.

In this case, however, epoxy resins do not show sufficient radiationresistance. In addition, in the future, radiation resistance isincreasingly required because the amount of radiation is estimated toincrease with growth of energy of accelerators. Furthermore, polyimidecan be listed as thermal fused layers with excellent radiationresistance, however, it has become a problem that the thermal fusedpolyimide is bonded at a high temperature, while polyimide which can bebonded at a low temperature is poor in heat resistance, adhesion, andresins squeezing out at pressing. To solve the above problems, adhesiveswhich can be bonded at low temperatures and have excellent radiationresistance have been needed.

Accordingly, it is an object of the present invention to provide apolyimide resin which is excellent in low water absorption, heatresistant for solders, heat resistance, and adhesion.

It is another object of the present invention to provide a resincomposition which comprises a polyimide resin capable of being cured tobe bonded at a relatively low temperature, and is soluble in solvent andexcellent in heat resistance and adhesion.

It is further another object of the present invention to provide anadhesive solution wherein a solvent is easily removable from a filmwhile keeping its heat resistance and adhesion, and a joining componentin a film state obtained by using the adhesive solution.

It is still another object of the present invention to develop anadhesive laminate film for wire rod coating which is excellent inflexibility and adhesion, and the like without any deterioration of thewire rod when coating with it.

DISCLOSURE OF THE INVENTION

The polyimide resin of the present invention is obtained by reactingtetracarboxylic acid dianhydride containing ester acid dianhydriderepresented by the general formula (1):

wherein X represents —(CH₂)_(k)—, or is a divalent group which comprisesan aromatic ring; k is an integer from 1 to 10; with diamine containingan aromatic diamine represented by the general formula (2):

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group; n may be an integer from 0 to 4; and R₁ whose number is nis the same or different; and/or an aromatic diamine represented by thegeneral formula (3):

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—, R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group, and are the same ordifferent, x, y, z, m, and n are each an integer from 0 to 4. A whosenumber is n (m+1) may be respectively the same or different.

Or the polyimide resin of the present invention is obtained by areaction between tetracarboxylic acid dianhydride containing ester aciddianhydride represented by the general formula (1):

wherein X represents —(CH₂)_(k)— or is a divalent group which comprisesan aromatic ring; k is an integer from 1 to 10); and aromatic diaminerepresented by the general formula (4):

wherein Y is at least one selected from the groups consisting of asingle bond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—; p and q are each an integer from 1 to 5.

Further, the polyimide resin of the present invention is obtained byreacting tetracarboxylic acid dianhydride containing ester-aciddianhydride represented by the general formula (1):

wherein X represents —(CH₂)_(k)— or is a divalent group comprising anaromatic ring; k is an integer from 1 to 10; with aromatic diaminerepresented by the general formula (4):

wherein Y is at least one selected from the groups consisting of asingle bond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—; p and q are each an integer from 1 to 5; andsiloxane diamine represented by the general formula (5):

Wherein R₅ and R₆ are each a divalent aliphatic group whose carbonnumber is from 1 to 4 or a divalent aromatic group, R₇, R₈, R₉, and R₁₀are each a monovalent aliphatic group whose carbon number is from 1 to 4or a monovalent aromatic group; n is an integer from 1 to 10.

Other general explanation of the polyimide resin of the presentinvention is that the polyimide resin is obtained by a reaction amongtetracarboxylic acid dianhydride containing 2,2-(4-hydroxyphenyl)propanedibenzoate-3,3′4,4′-tetracarboxylic acid dianhydride representedby the general formula (7):, and

aromatic diarine represented by the general formula (2):

Wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group; n is an integer from 0 to 4; R₁ whose number is n may bethe same or different, and/or diamine containing aromatic diaminerepresented by the general formula (3):

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—; R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group, and may be the sameor different; x, y, z, m, and n are each an integer from 0 to 4; and Awhose number is (m+1) may be respectively the same or different.

Tetracarboxylic acid dianhydride containing 2,2-(4-hydroxyphenyl)propanedibenzoate-3,3′4,4′-tetracarboxylic acid dianhydride representedby the general formula (7) can be adjusted to have a residual impuritiescontent of 1 wt % or lower.

These polyimide resins may have both a glass transition temperature from100° C. to 250° C. and water absorption of 1.5% or lower.

Further, the resin composition of the present invention comprises thepolyimide resin and a thermosetting resin.

The resin composition of the present invention may have water absorptionafter cured of 1.5% or lower.

Furthermore, the resin composition of the present invention may have aresidual volatile component of 3 wt % or lower.

Further, the polyimide resin may be a resin composition which is anamine-terminated polyimide oligomer.

The cured resin of the present invention obtained by curing theabove-mentioned resin composition may have water absorption of 1.5% orlower.

Its residual volatile component may be 3 wt % or lower.

The polyimide adhesive solution of the present invention is comprisedthe above polyimide resin, epoxy resin, and curing agent, wherein 50mole % or more of a dianhydride residue included in the polyimide resinis an ester-acid dianhydride residue represented by the general formula(1):

wherein X, represents —(CH₂)_(k)—, or is a divalent group whichcomprises an aromatic ring; and k is an integer from 1 to 10; and theorganic solvent may include a cyclic ether solvent.

The general description of the film-state joining component of thepresent invention is formed by laminating a thermosetting resin on oneside or both sides of a base film with a main constituent of the abovepolyimide resin.

Other general description of the film-state joining component of thepresent invention is formed by laminating the above resin composition onone side or both sides of the polyimide base film. Further, thefilm-state joining component of the present invention is obtained bydissolving the above resin composition in an organic solvent andapplying or flow casting the composition onto a support, andsubsequently depositing the film-like resin composition layer obtainedby peeling off a coating film from the support after being dried. Or thefilm-state joining component is obtained by dissolving the abovementioned resin composition in an organic solvent and applying or flowcasting the composition onto at least one side of the polyimide basefilm, and drying it subsequently. In addition, the film-state joiningcomponent of the present invention is obtained by applying the abovepolyimide adhesive solution by applying or flow casting onto the supportand peeling off the adhesive coating film from the support after beingdried. Or the film-state joining component is obtained by applying theabove polyimide adhesive solution or flow casting it onto at least oneside of the polyimide base film and drying it subsequently.

Moreover, the above mentioned film-state joining component may be usedfor the adhesive laminate film for wire rod coating.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective illustration view to explain a method forcoating a wire rod with an adhesive laminate film for wire rod coatingaccording to the present invention.

FIG. 2 is a perspective illustration view to explain another method forcoating a wire rod with an adhesive laminate film for wire rod coatingaccording to the present invention.

FIG. 3 is a perspective illustration view to explain still anothermethod for coating a wire rod with an adhesive laminate film for wirerod coating according to the present invention.

FIGS. 4(a) and 4(b) are perspective illustration views to respectivelyexplain a further method for coating a wire rod with an adhesivelaminate film for wire rod coating according to the present invention.FIG. 4(a) shows a coating process and FIG. 4(b) shows a status of thecoated laminate film after being processed.

FIGS. 5(a) and (b) are perspective illustration views to respectivelyexplain a still further method for coating a wire rod with an adhesivelaminate film for wire rod coating according to the present invention.

FIG. 6 is a cross-sectional view of the adhesive laminate film for wirerod coating after coating a wire rod according to the present inventionshown in FIG. 5.

FIG. 7 is a perspective illustration view to explain an adaptive examplefor particle accelerations of a wire rod coated with the adhesivelaminate film according to the present invention shown in FIGS. 5 to 6.

BEST MODE FOR CARRYING OUT THE INVENTION

The polyimide resin of the present invention is synthesized fromtetracarboxylic acid dianhydride containing ester acid dianhydriderepresented by the general formula (1) (wherein X is a divalent groupwhich comprises an aromatic ring) and diamine represented by the generalformula (2) and/or formula (3).

Ester acid dianhydride is represented by the general formula (1):

wherein X represents —(CH₂)_(k)—, or is a divalent group which comprisesan aromatic ring: and k is an integer from 1 to 10.

The polyimide resin using an ester acid dianhydride represented by thegeneral formula (1) has a superior characteristic in heat resistance ofsolders so as to its excellent water absorption factor. As a preferredexample of an ester acid dianhydride used in the present invention,2,2-bis (4-hydroxyphenyl) propanedibenzoate-3,3′,4,4′-tetracarboxylicacid dianhydride, p-phenylene-bis (trimellitic acid monoesteranhydride), 3,3′,4,4′-ethyleneglycol benzoate tetracarboxylic aciddianhydride, 4,4′-biphenylene-bis (trimellitic acid monoesteranhydride), 1,4-naphthalene-bis (trimellitic acid monoester anhydride),1,2-ethylene-bis (trimellitic acid monoester anhydride),1,3-trimethylene-bis (trimellitic acid monoester anhydride),1,4-tetramethylene-bis (trimellitic acid monoester anhydride),1,5-pentamethylene-bis (trimellitic acid monoester anhydride),1,6-hexamethylene-bis (trimellitic acid monoester anhydride) are named.These ester acid dianhydrides are used alone or in combination of two ormore.

Further, diamine to be used in the present invention is aliphaticdiamine or aromatic diamine represented by the general formula (2):

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group, and n is an integer from 0 to 4. R₁ whose number is n maybe the same or different; and/or diamine containing an aromatic diaminerepresented by the general formula (3):

wherein A is any one of bond groups selected from the groups consistingof a single bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—; R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, alkoxyl groups or a halogen group, and are the same ordifferent groups; x, y, z, m, and n are each an integer from 0 to 4; andA whose number is (m+1) may be the same or different.

These diamines may be used either alone or in combination of two ormore.

Examples of aliphatic diamines include 1,2-diaminoethane,1,3-diaminopentane, 1,3-diaminopropane, 1,4-diaminobutane,1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminohepthane,1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, or the like.

Examples of aromatic diamines represented by the general formulae (2)and/or (3) include o-phenylenediamine, m-phenylenediamine,p-phenylenediamine, 2,4-toluenediamine, 3,3′-diaminodiphenyl ether,3,4′-diaminophenyl ether, 4,4′-diaminophenyl ether,3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenyl methane,4,4′-diaminodipheylmethane, 3,3′-diaminobenzophenone,4,4′-diaminobenzophenone, 3,3′-diaminophenylsulfide,4,4-diaminodiphenylsulfide, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis(3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2-bis(4-(3-aminophenoxy) phenyl)propane, 2,2-bis(4-(4-aminophenoxy) phenyl)propane, 4,4′-bis (p-aminophenoxy) sulfone, 3,4′-bis (p-aminophenoxy)diphenylsulfone, 3,3′-bis (p-aminophenoxy) diphenylsulfone, 4,4′-bis(4-aminophenoxy) biphenyl, or the like.

Aromatic diamines are more preferably used than aliphatic diamines inview of heat resistance, or the like as diamine components in thepolyimide according to the present invention.

Further, aromatic diamines represented by the general formula (4) arepreferably used:

wherein Y is any one of bond groups selected from the groups consistingof a single bond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—. p and q are each an integer from 1 to 5.

A plurality of Y may be the same or two or more kinds of substituentgroups in diamines represented by the general formula (4). In addition,hydrogen of each benzene ring may be substituted by various substituentgroups as appropriate within the scope of the idea of the person in theart. Examples of the Substituent groups include methyl group, ethylgroup, and halogen group such as Br and Cl, but these substitutentgroups are not particularly limited.

Further, the diamines to be used for polyimide resins are siloxanediamines represented by the general formula (5) other than theabove-mentioned diamines:

wherein R₅ and R₆ are each a divalent aliphatic group whose carbonnumber is from 1 to 4 or a divalent aromatic group, R₇, R₈, R₉, and R₁₀are each a monovalent aliphatic group whose carbon number is from 1 to 4or a monovalent aromatic group, n is an integer from 1 to 10.

More particularly, the diamines include α,{overscore (ω)}-bis(3-aminopropyl) polydimethylsiloxane, {overscore (ω)}, {overscore(ω)}-bis (2-aminoethyl) polydimethylsiloxane, {overscore (ω)},{overscore (ω)}-bis (3-aminopropyl) polydimethylsiloxane, {overscore(ω)}, {overscore (ω)}-bis (4-aminophenyl) polydimethylsiloxane,{overscore (ω)}, {overscore (ω)}-bis (4-amino-3-methylphenyl)polydimethylsiloxane, {overscore (ω)}, {overscore (ω)}-bis(3-aminopropyl) polydimethylsiloxan, or the like, but these are notparticularly limited.

When siloxane diamine is mixed with the diamines to be used, each of theratio of diamine is not particularly limited, however, the ratio ofsiloxane diamine to total diamines is within the range of 1 to 30 mole %is preferable. The polyimide resins containing siloxane diamineaccording to the present invention are easily handled when used as anadhesive because the solubility to a low boiling point solvent rises.When the ratio of siloxane diamine is less than 1 mole %, the solubilityto a low boiling point solvent is poor. When the ratio is more than 30mole %, heat resistance in the polyimide resin compositions obtained ispoor.

Particularly, a bond of diamines represented by the general formula (4)and an amino group in the meta position represented by the followinggeneral formula (6) leads to improvement of the solubility to an organicsolvent of the polyimide resins generated and excellent usefulness whenused as an adhesive, and the like:

wherein Y is any one selected from the groups consisting of a singlebond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—, —C(CF₃)₂—,or —C(═O)O—. p and q are each an integer from 1 to 5.

Diamines represented by the above general formula (4) and (6) may beused alone or in combination of two or more.

Ester acid dianhydrides represented by the general formula (1) are usedas a comment in the polyimide resins according to the present invention:

wherein X represents —(CH₂)_(k)—, or is a divalent group which comprisesan aromatic ring, k is an integer from 1 to 10.

Tetracarboxylic acid dianhydrides containing 2,2′bis (4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylic acid dianhydride (hereafterreferred to as ESDA) represented by the following general formula (7)and diamines may be imidized to obtain:

Furthermore, tetracarboxylic acid dianhydrides which contains residualimpurities in the total of tetracarboxylic acid dianhydrides includingESDA of 1 wt % or lower may be used for the polyimide resins of thepresent invention. The polyimide resins can be obtained by theimidization of diamines and tetracarboxylic acid dianhydrides containingESDA which have preferably 1 wt % or lower of their residual impurities,more preferably 0.5 wt % or lower.

The residual impurities in the present invention mean any materialsexcept tetracarboxylic acid dianhydride and mainly trimellitic anhydrideor its derivatives. For example, the following compound (1):

or the compound (2) is contained in the residual impurities:

The residual impurities act as a polymer inhibitor when polyamic acidwhich is a polyimide precursor of polyimide is purified. Accordingly,when the content of the residual impurities contained in tetracarboxylicacid dianhydride or ESDA exceeds 1%, no sufficient degree ofpolymerization to form a polyimide film can be obtained because ofincreased polymer inhibitor actions, but a film which has fewself-support properties and vulnerable can be obtained.

A method for limiting the content of the residual impurities containedin ESDA to 1% or lower includes a method for recrystallizingtetracarboxylic acid dianhydride or ESDA represented by the generalformula (7) with a mixed solvent (Patent Publication No. 2-240074):

An explanation will be given to concrete methods using ESDA as anexample, crude material 100 weight parts of ESDA, a solvent belonging togroup (A), and a solvent belonging to group (B) or the range from 100 to1000 weight parts of aliphatic anhydride are mixed to be dissolved byheating between 100° C. and 200° C. Continuously, ESDA crystals aredetected by gradually cooling to the roan temperature. These crystalsare filtered and separated by a known method and then dried to obtainESDA having residual impurities of 1 wt % or lower.

A solvent belonging to group (A) and a solvent belonging to group (B)may be respectively used alone or in combination. Further, whenaliphatic anhydrides are used for recrystallization, consecutiveprocessing is also possible with a solvent belonging to the group (A)and/or a solvent belonging to the group (B).

The solvent belonging to the group (A) includes a hydrocarbon solventwhich is inactive to ESDA and has ESDA solubility of 3 g/100 g or lessat 25° C., more particularly, aromatic hydrocarbon, such as benzene,toluene, xylene, ethyl benzene, and isopropyl benzene, and aliphatichydrocarbon, such as heptane, hexane, octane, and cyclohexane.

The solvent belonging to the group (B) includes a solvent which isinactive to ESDA and has ESDA solubility of 5 g/100 g or more at 25° C.,more particularly, ketones, such as diisopropyl ketone, methylethylketone, acetylacetone, acetophenone, and cyclohexanone, and ethers, suchas diisopropyl ether, ethylbutyl ether, and dichloroisopropyl ether, andesters, such as ethyl acetate, butyl acetate, cellosolve acetate,carbitol acetate, methyl aceto acetate, methyl propionate, methylbutyricate, and methyl phthalate.

An example of aliphatic anhydride includes acetic anhydride, but it isnot limited.

The mixture ratio of the solvent belonging to the group (A) and thesolvent belonging to the group (B) is selected within the range of(A):(B)=1:9 to 9:1.

ESDA and other tetracarboxylic acid dianhydride can be used incombination to the extent which does not deteriorate characteristics ofpolyimide.

Examples of tetracarboxylic acid dianhydrides to be used in combinationinclude pyromellitic acid dianhydride, benzophenonetetracarboxylic aciddianhydride, biphenyltetracarboxylic acid dianhydride,diphenylethertetracarboxylic acid dianhydride,naphthalenetetracarboxylic acid dianhydride, anddiphenylsulfonetetracarboxylic acid dianhydride, or the like. They maybe used in combination of two or more together with ESDA. ESDA iscontained 5 wt % or higher and 100 wt % or lower in totaltetracarboxylic acid dianhydride, preferably contained 10 wt % or higherand 100 wt % or lower in total tetracarboxylic acid dianhydride. ESDAmay be more preferably contained 30 wt % or higher and 100 wt % or lowerin total tetracarboxylic acid dianhydride.

The polyimide resin of the present invention is obtained by dehydrationand ring closure of a polyamic acid polymer as its precursor. Thepolyamic acid polymer is obtained by a substantial equimolarpolymerization of ester acid dianhydride represented by the aboveformula (1) and one kind or more of diamine components represented bythe above formula (2) and/or (3), particularly the formula (4) and/or(6) or (4). Polymerization is generally performed in an organic polarsolvent. A substantial equimolar herein means that the ratio betweendianhydride and diamine is within the range of 0.98:1 to 1.02:1.

To synthesize a polyimide resin, a polymerization is performedpreferably in the inactive atmosphere, such as argon gas, nitrogen gasby dissolving on diffusing at least one kind of diamine componentrepresented by the above-mentioned general formula (2) and/or (3),particularly the general formula (4) and/or (6) and a dianhydrideselected from ester acid dianhydride represented by the general formula(1) in an organic polar solvent or diffused to obtain a solution of apolyamic acid polymer. “Dissolving” herein includes a case wherein thesolute is in the same status to be substantially dissolved by beingevenly dispersed or diffused in a solvent in addition to the case thesolute is perfectly dissolved in the solvent.

The order of addition of each monomer when the above mentioned polyamicacid polymer is polymerized may be that a dianhydride is previouslyadded in the organic polar solvents and then the diamine component maybe added. Further, a part of diamine component may be first added in theorganic polar solvent as appropriate and the next, a dianhydride may beadded, and further the reminder of the diamine component may be added toobtain a solution of a polyamic acid polymer. Any other variety ofaddition methods which are known to those skilled in the art may beused.

An organic polar solvent is preferably used when a polyamic acid polymeris synthesized. Concrete examples of organic polar solvents include, forexample: sulfoxide solvents, such as dimethyl sulfoxide, diethylsulfoxide, formamide solvents, such as N,N-dimethylformamide, andN,N-diethylformamide, acetamide solvents, such as N,N-dimethylacetamideand N,N-diethylacetamide, a pyrrolidone solvent, such asN-methyl-2-pyrrolidone, phenol solvents, such as phenol, o-, m-, orp-cresol, xylenol, halogenated phenols, and catechol, orhexamethylphospholamide, γ-butylolactone, or the like. These organicpolar solvents and aromatic hydrocarbon, such as xylene or toluene canalso be used in combination as necessary.

The polyamic acid polymer obtained in this manner is dehydrated for ringclosure, for example, by a thermal or chemical method to afford thepolyimide resin of the present invention. The imidization methodsinclude, for example, the thermal imidization to dehydrate the polyamicacid solution by heat treatment and the chemical imidization todehydrate the solution by a dehydrating agent. Either of them may beused.

The method for thermally dehydrating for ring closure is achieved byevaporating the solvent of the above-mentioned polyamic acid solution.Further, the method for chemically dehydrating for ring closure isachieved by adding a dehydrating agent and a catalyst in amounts notsmaller than the stoichiometric amounts to the above-mentioned polyamicacid polymer and evaporating an organic solvent. It is preferable toevaporate the organic solvent under temperature conditions of 160° C. orlower within the range of time for about 5 to 90 minutes. Furthermore,the heating temperature is selected within the range between roomtemperature and about 250° C. as appropriate. Imidization may be carriedout at room temperature. Gradual heating is preferable. Examples ofdehydrating agents to be used when a chemical method is carried outinclude: aliphatic anhydride such as acetic anhydride, and aromaticanhydride. And examples of catalysts include: aliphatic tertiary amines,such as triethyl amine, aromatic tertiary amines, such as heterocyclictertiary amines, such as pyridine and isoquinoline.

Thermal imidization and chemical imidization may be used in combination.

The polyimide resin of the present invention obtained in this manner haslow water absorption and the glass transition temperature at arelatively low temperature. Specifically, it is preferable to have theglass transition temperature from 100° C. to 250° C., a water absorptionfactor of 1.5% or lower, and a dielectric constant of 3.2 or lowerbecause of excellent workability, durability, and insulation properties.

The glass transition temperature of 100° C. or lower is not preferablebecause of poor heat resistance. In addition, the glass transitiontemperature of 250° C. or higher is not preferable because of highworking temperature in view of workability. Since the glass transitiontemperature of the polyimide resin of the present invention is withinthe range of 100° C. to 250° C., a lamination of the polyimide resin ata temperature close to this temperature range makes it possible to bedissolved. In addition, the polyimide resin may be preferably usedwithin this temperature range from the viewpoint of easy curing of athermosetting resin. The polyimide resin may be more preferably usedwithin the range of 100° C. to 200° C.

Although the polyimide resin having water absorption of over 1.5% is notpreferable because it may have swelling, the polyimide resin accordingto the present invention having water absorption of 1.5% or lower ispreferable from the viewpoint of little deterioration of a film functioncaused by absorption of water. More preferably, the polyimide resin haswater absorption of 1.3% or lower, particularly preferable is 1.0% orlower.

Further, the polyimide resin having a dielectric constant of over 3.2 isnot preferable because it is poor in insulation properties, but thepolyimide resin according to the present invention is preferable becauseits dielectric constant can be 3.2 or lower from the viewpoint of fewdielectric loss when coating the wire rod to pass electric current. Morepreferably, it is 3.0 or lower.

Further, to improve adhesion properties, a silane coupling agent and anonionic surface active agent, or the like may be added to the polyimideresin according to the present invention as appropriate.

Exemplary silane coupling agents to be used include:vinyltrichlorosilane, vinyltriethoxysilane,metaachroxypropyltrimethoxysilane, or the like. The compounded amount isfrom 0.01 to 5 wt % to the total amount of the polyimide resin.Exemplary titanic coupling agents include: isopropyltriisostearoyltitanate and isopropyltridecylbenzenesulfonyltitanate, orthe like. The compounded amount is within the range of 0.01 to 5 wt % tothe total amount of the polyimide resin.

Exemplary nonionic surface active agents include: fatty acidmonoglycerin ester, aliphatic polyglycol ester, and aliphaticalkanolamide, or the like. The compounded amount is 0.01 to 5 wt % tothe total amount of the polyimide resin.

Next, the resin composition of the present invention is to be one ofstructure components which comprise the above-mentioned polyimide resin.Therefore, when the resin composition of the present invention is cured,in a preferred embodiment, it becomes possible to have very low waterabsorption of 1.5% or lower, more preferably, 1.3% or lower, 1.0% orlower is particularly preferable. Further, when the resin composition iscured, the use of epoxy resin makes it possible to provide excellentadhesion in addition to polyimide resin's excellent heat resistance andlow water absorption.

The resin composition of the present invention can be obtained by evenlymixing by stirring the polyimide resin to be obtained in theabove-mentioned manner and thermoplastic resin, such as epoxy resin anda curing agent, and other components. In the resin composition of thepresent invention, particularly, with the use of epoxy resin, furtherexcellent adhesion in addition can be provided to characteristics of thepolyimide resin to be used in the present invention.

Bismaleimide, bisarylnadiimide, phenol resin, and cyanate resin, or thelike may be used as thermoplastic resin to be used herein, but an epoxyresin is particularly preferred to be used in view of the balance of itscharacteristics. An arbitrary epoxy resin is usable in the presentinvention. For example, bisphenol epoxy resins, halogenated bisphenolepoxy resins, phenolnovolak epoxy resins, halogenated phenolnovolakresins, arkylphenolnovolak epoxy resins, polyphenol epoxy resins,polyglycol epoxy resins, alicyclic epoxy resins, cresolnovolak epoxyresins, glycidylamine epoxy resins, urethane denatured epoxy resins,rubber denatured epoxy resins, and epoxy denatured polysiloxane, or thelike can be used. Specifically, the examples include: Bisphenol A-typeresins, such as Epikote 828 (manufactured by Shell InternationalChemicals Corporation), orthocrezol novolak resins, such as 180S65(manufactured by Shell International Chemicals Corporation), Bisphenol-Anovolak resins, such as 157S70 (manufactured by Shell InternationalChemicals Corporation), trishydroxyphenyl methane novolak resins, suchas 1032H60 (manufactured by Shell International Chemicals Corporation),naphthalene aralkyl novolak resins, such as ESN375, tetraphenolethane1031S (manufactured by Shell International Chemicals Corporation),YGD414S (Tohto Chemicals Corporation), trishydroxyphenyl methaneEPPN502H (Nippon Kayaku Co., Ltd.), special Bisphenol VG3101L (MitsuiChemicals, Inc.), special naphthol NC7000 (Nippon Kayaku Co., Ltd.), andglycidylamine type resins, such as TETRAD-X and TETRAD-C (Mitsubishi GasChemical Co., Inc.), or the like, the resins which include two or moreepoxy groups are particularly preferable because of excellent reaction.The resins having epoxy equivalent of 250 or less are preferable becauseof enhancement of its adhesion properties. Epoxy resins may be used incombination with thermoplastic resins, such as phenol resins, cyanateresins, and the like. The epoxy equivalent is obtained by dividing themolecular weight of the epoxy resins by the number of epoxy groups.

The mixture ratio of thermosetting resins, particularly epoxy resins arefrom 1 to 50 weight parts to 100 weight parts of polyimide which is athermoplastic resin, the weight parts from 5 to 30 are preferably added.When the weight parts are too few, the adhesive strength is low, butwhen they are too many, they are poor in flexibility, heat and radiationresistance as well.

The resin composition of the present invention may be used incombination of an epoxy curing agent, such as a dianhydride type,amine-type, and imidazole type, an accelerator, or various types ofcoupling agents, as well as the above mentioned thermosetting resins inaccordance with demands for improving absorption, heat resistance, andadhesion properties, or the like may be used in combination.

In the present invention, the polyimide resin contained as one ofembodiments in the resin composition may be amine-terminated polyimideoligomer.

The amine-terminated polyimide oligomer can be obtained by dehydratingpolyamic acid oligomer having amine terminal which is a precursor forring closure. The amine-terminated polyamic acid oligomer can beobtained by polymerizing ester acid dianhydride represented by the aboveformula (1) and at least one kind of diamine component represented bythe above formula (4) and/or (6) by a mixture which becomessubstantially an excess. Preferably, the polyamic acid oligomer can beobtained, for example, by the polymerization of a 1-mole ester aciddianhydride and from 1.02 to 1.1 mole of a diamine component. Thepolymerization is ordinarily performed in an organic polar solvent.

To synthesize the polyimide oligomer, in the inactive atmosphere, suchas argon gas and nitrogen gas, at least one kind of diamine representedby the formula (4) and/or (6), and a dianhydride selected from esteracid dianhydride represented by the formula (1) are dissolved ordiffused in the organic polar solvent to perform a polymerization andthen the polyamic acid oligomer solution can be obtained. The synthesisprocess may be carried out by the similar method as the polyimide resinaccording to the present invention.

The polyimide oligomer preferably has a number average molecular weightof 2,000 to 50,000, more preferably 3,000 to 40,000, and furtherpreferably 5,000 to 30,000. If the molecular weight is 2,000 or greater,mechanical strength required for curing substances obtained by curingthe composition will be retained. Further, if the polyimide oligomerhaving an amino group as a terminal has the number average of molecularweight of smaller than 50,000, the amount of amino group to be areaction point with epoxy resin is relatively suitable for an epoxygroup and has appropriate bridge density, so that it has stability fromthe viewpoint of structure because of no empty parts. This leads toprevent the penetration of solvents, so that peeling strength retentionafter conducting a PCT (Pressure Cooker Test), which is a reliabilitytest for electronic materials, can be improved.

Thus-obtained amino group of amine-terminated polyimide oligomer andepoxy group of epoxy resin are bridged by a chemical reaction togenerate a new chemical bond at multi-points. Polyimide oligomer,therefore, exerts the similar reaction effect to a curing agent of epoxyresin to increase the bridge density and decrease water absorption.Additionally, the polyimide oligomer part that is not reactive to epoxyresin has a relatively low glass transition temperature, so that itenables low water absorption and law temperature adhesion as a whole.The amine-terminated polyimide oligomer is characterized in that it maybe chemically bonded to epoxy resin. In the resin composition of thepresent invention, the amine terminal may be chemically bonded to epoxyresin, or may not be bonded to epoxy resin. The effects of the presentinvention can be obtained, if only the chemical bond between the amineterminal of polyimide oligomer and epoxy resin is formed before theresin composition for adhesion is finally cured. Accordingly, in theresin composition of the present invention before curing, the effects ofthe present invention can be obtained regardless of whether or not theamine terminal of the polyimide oligomer is chemically bonded to epoxyresin.

For example, when the resin composition is used as a flexible copperclad laminate, there is an advantage that a chemical bond between anamine terminal of the polyimide oligomer and the epoxy resin results inlittle penetration of solvents because of its elaborate structure havingmultiple cross-linking points. For example, the peeling strengthretention after the PCr (Pressure Cooker Test), which is a reliabilitytest for electronic materials, can bring about a high retention, such aspreferably 60% or greater, more preferably 70% or greater, furtherpreferably 80% or greater.

In another preferable embodiment of the resin composition in the presentinvention, the residual volatile component of an organic solventincluded after curing the resin composition may contain 3 wt % or lower.One kind or at least two kinds of solvents included in the resincomposition of the present invention are not particularly limited, ifonly they dissolve a polyimide and an epoxy resin, but they are limitedto the kind and amount that may limit the residual volatile component to3 wt % or lower. Further, the solvents having a low boiling point at160° C. or lower is preferable from the viewpoint of economics andworkability. Additionally, “solvents having a low boiling point” hereinmean the solvents having a boiling point at 160° C. or lower. Thesolvents have preferably a boiling point at 130° C. or lower, morepreferably at 105° C. or lower. These solvents having a low boilingpoint preferably include: tetrahydrofuran (hereinafter referred to asTHF. Boiling point: 66° C.), 1,4-dioxane (hereinafter referred to asdioxane. Boiling point: 103° C.), 1,2-dimethoxyethane boiling point 84°C.). They may be used alone or may be used in combination of two kindsor more.

The residual volatile component in the curing substance which wasobtained by curing the resin composition may be 3 wt % or lower,preferably 2 wt % or lower, and the component may be particularlypreferable to be 1 wt % or lower.

The residual volatile component may be easily measured, for example, bythe gas chromatography method, or the like. A curing substance tomeasure the residual volatile component is prepared as mentioned below.An adhesive is cast onto a glass plate. After drying at 100° C. for 10minutes, the adhesive is peeled off from the glass plate to set on asteel frame, and a sheet having a thickness of 25 μm is obtained afterdrying at 150° C. for 20 minutes. The obtained sheet is sandwichedbetween a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and a flexible copperclad laminate is obtained after giving pressure by heating at 200° C.under a pressure of 3 Mpa for 20 minutes. The cured adhesive within thislaminate is dissolved with a solvent different from the solvents withinthe cured adhesive to prepare a sample of certain concentration (forexample, 5 wt %). And then the weight of the residual volatile componentcan be measured using a detector such as FID by vaporizing in thecarrier gas. Solvents, which are estimated to be contained in heresidual volatile component, are solved in the other solvent to beprepared solutions in various concentrations. Each solution is vaporizedin the carrier gas within a column for gas chromatography. A calibrationcurve is created. And then the weight of the residual volatile componentcan lead to an easy measurement according to the detector such as FID ismade.

The residual volatile component in the curing substance which wasobtained by curing the resin composition is reduced to be 3 wt % orlower, preferably 2 wt % or lower, and particularly preferable to be 1wt % or lower. This leads to excellent adhesion when using the resincomposition as an adhesive, for example, as a flexible copper laminatedplate. For example, it becomes possible to attain a high peelingstrength retention, preferably 60% or greater, more preferably 70% orgreater, further preferably 80% or greater after conducting a PCT(Pressure Cooker Test) which is a reliability test for electronicmaterials.

Adjusting the mixture of the resin composition allows the waterabsorption of the resin composition to be easily adjusted by thoseskilled in the art. In a preferred embodiment, the water absorption ofthe curing substance obtained by the composition of the presentinvention is 1.5% or lower.

Moreover, the resin curing substance to measure the water absorption isprepared as mentioned below. An adhesive is cast onto a glass plate.After drying at 100° C. for 10 minutes, the adhesive is peeled off fromthe glass plate to set on a steel frame, and a sheet having a thicknessof 25 μm is obtained after drying at 150° C. for 20 minutes. Theobtained sheet is sandwiched between a polyimide film (Apical 50AH,manufactured by Kaneka Corporation) and a copper foil of 25 μmthickness, and a flexible copper clad laminate is obtained after givingpressure by heating at 200° C. under a pressure of 3 MPa for 20 minutes.The water absorption of the cured adhesive within the laminate may bemeasured in an arbitrary method in the publicly known art. For example,it can be calculated by, for example, measurement based on ASTM D570.

The resin composition according to the present invention is not limitedin its producing method and timing of mixing each component. Morespecifically, a resin solution which comprises a thermoplastic polyimideand a thermosetting resin may be obtained by adding the thermosettingresin as it is to the thermoplastic polyimide solution. Or the resinsolution may be adjusted by adding a low boiling point solvent to thethermoplastic polyimide solution and further adding a thermosettingresin to be stirred for mixing. The resin composition of the presentinvention may be obtained by throwing a polyimide solution into a poorsolvent used at the time of polymerization of polyamic acid to remove anon-reacted monomer by depositing the polyimide resin to be dried, andthen drying to obtain a solid polyimide resin as well. Although the poorsolvent dissolves the solvent well, the polyimide has an attribute to bedifficult to be dissolved. Typical examples are acetone, methanol,ethanol, isopropanol, benzene, methyl cellsolve, methyl ethyl ketone, orthe like, which are not limited.

In addition, it is not particularly limited that the solid-statethermoplastic polyimide resin purified as described above may beconverted in a filter refined varnish state by dissolving again thispurified polyimide resin together with the above thermosetting resin inan organic solvent when being used. The organic solvent used at thistime is not particularly limited and any known organic solvents thatthose skilled in the art can be used.

In the conventional polyimide-type adhesive, while its adhesion was notstrong enough for metals such as a copper foil and resin films such aspolyimide, and the mixture with an epoxy resin was difficult due to itslimited solubility, in the resin composition of the present invention,its adhesion with metal foils such as a copper foil or polyimide filmsis superior. Further, the resin composition of the present invention hassuperior workability because of having superior solubility in organicsolvents. Furthermore, such superior solubility in organic solventsleads to properties such as adhesiveness at a low temperature. Morespecifically, thee resin composition has an excellent low waterabsorption of 1.5% or lower, preferably 1.3% or lower, furtherpreferably 1.0% or lower, and it can be bonded as an adhesive at thetemperature of about 250° C. or lower due to its excellent solder heatresistance and heat resistance, as well as excellent adhesion.Accordingly, the resin composition has superior workability. Forexample, the polyimide and epoxy resin solutions obtained by imidizationof a polyamic acid polymer can be used in a sheet state directly. Forexample, the resin composition can be used as it is as a printed circuitboard, or the like. Moreover, it has properties preferably used forelectronics, particularly, a flexible printed circuit board, a tape forTAB, a composite lead frame, lamination materials, or the like as alamination material.

When an amine-terminated polyimide oligomer is used as a polyimide, thecomposition of the present invention has a sophisticated or elaboratestructure having multiple cross-linking points in the resin compositionso that the amine termination may be chemically bonded to the epoxyresin, which results in few permeation of the solvent. As a result, itbecomes possible to attain a high peeling strength retention, preferably60% or greater, more preferably 70% or greater, further preferably 80%or greater after conducting a PCT (Pressure Cooker Test) which is areliability test for electronic materials. Moreover, the composition hasexcellent solder heat resistance, as well as excellent heat resistanceand adhesion, and when it is used as an adhesive, a composition whichcan be bonded at a relatively low temperature, for example, not higherthan about 250° C. is provided.

Next, the polyimide-type adhesive solution according to the presentinvention is obtained by dissolving the obtained thermo-plasticpolyimide resin of the present invention and the above-mentioned epoxyresin and curing agent in an organic solvent, but particularly, thepolyimide-type adhesive solution of the present invention using anorganic solvent including cyclic ether solvent has strong adhesion whenused for laminating layers because the solvent can be removed by dryingat a relatively low temperature.

Tetrahydrofuran (THF), 1,4-dioxane, and dioxolane may be preferably usedas cyclic ether solvents. Further, when a mixed organic solvent preparedby mixing a plurality of solvents is used, it is desirable to combinethe organic solvent with a polar organic solvent. The effects of thepresent invention, however, appear more easily when including a cyclicether solvent of 30 wt % or higher, preferably 50 wt % or higher. Amongorganic polar solvents in combination with a cyclic ether solvent aresulfoxide-type solvents, such as diethyl sulfoxide and diethylsulfoxide, formamide-type solvents, such as N, N-dimethylformamide andN,N-diethyl formamide, and acetamide-type solvents, such as N,N-dimethylacetamide and N,N-diethyl acetamide.

The thermoplastic polyimide resin used for the adhesive solution of thepresent invention is characterized in that 50 mole % or more ofdianhydride residue contained in the particle is an ester aciddianhydride residue represented by the general formula (1):

Wherein X represents —(CH₂)_(k)—, or is a divalent group which comprisesan aromatic ring, k is an integer from 1 to 10. It has excellentsolubility in the above organic solvent because of its structure.

Preferable examples of anhydrides represented by the general formula (1)are 2,2-bis (4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylic acid anhydride,p-phenylenebis (trimellitic acid monoester anhydride),4,4′-biphenylene-bis (trimellitic acid monoester anhydride),1,4-naphthalene-bis (trimellitic acid monoester anhydride),1,2-ethylene-bis (trimellitic acid monoester anhydride),1,3-trimethylene-bis (trimellitic acid monoester anhydride),1,4-tetramethylene-bis (trimellitic acid monoester anhydride),1-5-pentamethylene-bis (trimellitic acid monoester anhydride),1,6-hexamethylene-bis (trimellitic acid monoester anhydride), or thelike. However, 2,2-bis (4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylic acid dianhydride representedby the general formula (7) is particularly preferable:

Moreover, diamine components to allow to react with the abovedianhydride are not limited, if only they are diamines used for theabove polyimide resin, but a diamine compound, particularlybis(aminophenoxyphenyl) sulfone represented by the general formula (4)is preferable:

wherein Y is any one selected from the groups represented by a singlebond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—, —C(CF₃)₂—,and —C(═O)O—. p and q are each an integer from 1 to 5.

Furthermore, in the general formula (4), a plurality of Y may be thesame or different between each of repeating units, and hydrogen of eachbenzene ring may be substituted by various types of substituted groupsas appropriate within the scope of the idea of the person in the art.Typical examples are methyl group, ethyl group, hydrocarbon group, andhalogen group such as Br and Cl, but these substituent groups are notparticularly limited. In addition, since the thermoplastic polyimidecontaining diamine compounds has superior solubility in an organicsolvent, an adhesive solution which is superior in workability ispreferably obtained from the diamine compound represented by the generalformula (6) having an amino group in the meta position out of thediamine compounds represented by the general formula (4). The diaminecompounds represented by the general formula (4) may be used incombination of two or more kinds.

Polyamic resins obtained from the above-mentioned diamine compounds andester acid dianhydrides are soluble to the organic solvents includingthe above-mentioned cyclic ether solvents which are insoluble orslightly dissolved to most of conventional thermoplastic polyimides.

The polyimide-type adhesive solution according to the present inventiondissolves the above polyimide resin and the above epoxy resin in theorganic solvent including the above cyclic ether solvent. The mixtureratio of epoxy resins is from 1 to 50 weight parts to 100 weight partsof polyimide which is a thermoplastic resin, the weight parts from 5 to30 are preferably added. When the weight parts are too few, the adhesivestrength is low, but when they, are too many, they are poor inflexibility, heat resistance and radiation resistance as well.

Other curing agents, accelerators, or various types of coupling agentsmay be used in combination. The concentration of the adhesive solutionis from 5 to 50 wt % to the solid component whose denominator is thesolution weight (thermoplastic polyimide+epoxy resin+curing agent),preferably from 10 to 40 wt %, from 15 to 30 wt % is particularlypreferred. Procedures of dissolution may be decided as appropriate inview of workability, and the like.

Next, one of embodiments of the joining component in a film stateaccording to the present invention is that the thermosetting resin isobtained by laminating the thermosetting resin onto one side or bothsides of a base film which comprises the above obtained thermoplasticpolyimide resin to dry by heating. Or after removing the solvent bycasting the above thermosetting resin on a support to be,a sheet, thejoining component in a film state can be obtained by attaching the resinto the base film which comprises the thermoplastic polyimide resin.

Furthermore, the thickness of the thermosetting resin laminated on theabove polyimide film is preferably within the range of 0.5 to 5 μm, morepreferably within the range of 0.5 to 3 μm. When the thickness is 0.5 μmor less, its adhesion is not strong enough, and when the thickness is 5μm or more, its mechanical strength is weak, so that the film becomesbrittle.

The other embodiment of the film-state joining component according tothe present invention can be obtained by laminating the resincomposition prepared by evenly mixing with stirring a thermoplasticpolyimide resin, a thermosetting resin, and the other components of thesurface of the polyimide film on one side or both sides. Specifically,the resin composition solution comprising the thermoplastic polyimideand the thermosetting resin used in the present invention, is obtainedby dissolving the thermoplastic polyimide in a solvent to be a polyimideresin solution, and then adding the thermoplastic polyimide and theother components, and is applied onto the polyimide film by being dried.Or the resin composition solution obtained in such a manner is appliedby flow casting on a support, and the solution may be laminated to thepolyimide film as well after removing the solvent to be a sheet.

Generally known Apical, Kapton, Uplex, and the like may be used for apolyimide film for laminating a resin composition layer, but they arenot limited. The thickness of the polyimide film may be selected asappropriate when used. Further the thickness of the resin compositionlayer which comprises a thermoplastic polyimide and a thermosettingresin laminated on the above polyimide film may be selected asappropriate in accordance with needs when used, but the thickness ispreferably within the range of 5 to 30 μm. When the thickness is toothin, its adhesion may be deteriorated, but when the thickness is toothick, it may cause difficulties in removing the organic solvent bydrying, which leads to foaming.

The bonding conditions of the joining component in a film state of thepresent invention may be enough, if only the joining component can besufficiently bonded and cured. For one example, the component may beheated at a temperature from 150 to 250° C. under a pressure from 0.1 to10 MPa for 5 to 20 minutes.

The film-state joining component according to the present invention maybe used, for example, when metal foils, such as a copper foil, analuminum foil, 42 alloy, the other film, and a printed circuit board,and the like are bonded by heating and giving pressure. The kind of theother film is not particularly limited, and for example, a polyimidefilm and a polyester film, and the like are used. Moreover, the bondingconditions in this case are not particularly limited, if only theconditions are good enough for the film to be bonded and cured. Moreparticularly, it is preferable to heat at a temperature from 150 to 250°C. under a pressure from 0.1 to 10 MPa for 5 to 20 minutes, but thepreferred embodiment is not limited to these conditions. As describedabove, the film-state joining component of the present invention ispreferably used for a flexible printed circuit board, a tape for TAB(Tape automated bonding), a composite lead frame, and laminationmaterials, or the like. Since the film-state joining component accordingto the present invention has superior properties, such as workability ata low temperature, flexibility, and radiation resistance, the joiningcomponent can be used as an adhesive laminate film for wire rod coating,particularly suitable for a wire rod coating for superconductivity.

The adhesive laminate film for wire rod coating according to the presentinvention is constructed by depositing a bonded layer which comprises athermosetting resin and the above obtained thermoplastic polyimide resinfilm onto a polyimide film. Generally known Apical, Capton, and Uplex,and the like may be used for the polyimide film on which the bondedlayer is laminated, but they are not limited. Further, the polyimidefilm has a thickness within the range of 5 to 300 μm, preferably withinthe range of 10 to 125 μm.

The bonded layer which comprises 4 thermoplastic polyimide and athermosetting resin laminated on the above polyimide film has athickness within the range of 1 to 20 μm, preferably within the range of3 to 10 μm.

Next, a method for obtaining the adhesive laminate film for wire rodcoating is, for example, to apply the film-like resin composition of thepresent invention, which comprises the thermoplastic polyimide resinobtained as described above and the thermosetting resin, onto the otherpolyimide film and perform thermocompression bonding.

In addition, the adhesive laminate film for wire rod coating may beobtained by overlapping the thermoplastic polyimide resin and thefilm-state thermosetting resin of the present invention formed with asheet of released paper to perform thermo compression bonding, and thereleased paper maybe peeled off when used.

Further, the desired adhesive laminate film for wire rod coating may beproduced by casting the solution of the resin composition of the presentinvention which comprises a thermoplastic polyimide and a thermosettingresin in an organic solution, particularly the adhesive solution of thepresent invention, directly onto a polyimide film and drying.

The obtained adhesive laminate film for wire rod coating according tothe present invention is provided for coating the wire rod, for example,is subsequently rolled up, or rolled up after a film as a spacer, suchas polyethylene terephthalate, polypropylene, and polyethylene, isdisposed on its the bonded layer side.

Such coating of the adhesive laminate film for wire rod coating isperformed by selecting as appropriate from methods usually performed.Examples are as mentioned below. For example, as shown in FIG. 1, afteran adhesive laminate film for wire rod coating 10 with a particularwidth is wrapped around the rim of a wire rod 12 in a spiral state sothat both ends of the laminate film 10 may be overlapped, heat at apredetermined temperature to bond a polyimide film 16 to the wire rod 12via a bonded layer 14. Or as shown in FIG. 21, the adhesive laminatefilm 10 may be wrapped around the wire rod 12 to keep both edges of thelaminate film 10 from overlapping. Moreover, as shown in FIG. 3, it isalso possible to form the laminate film 10 having a width which isslightly longer than the rim of the wire rod 12 to wrap the laminatefilm 10 along the wire rod 12 with the ends being bonded or pressed.

As shown in FIG. 4(a), the laminate film 10 is wrapped around the rim ofthe wire rod 12 with the bonded layer 14 outside, and the other film 18without adhesion is further wrapped on the outside with the ends of thefilm 18 overlapped slightly or kept a space between them. And then thebonded layer 14 is fused by heating under a pressure, as well as bondingthe polyimide film 16 in the overlapped portion of the ends of thelaminate film 10, the other film 18 wrapped outside may be bonded to theboned layer 14. According to such method, as shown in FIG. 4(b), thelaminate film of the present invention is bonded to the other film 18 tobe formed in a tube state, so that the laminate film 10 can be coated onthe rim of the wire rod 12 without a close contact with the wire rod 12.This structure is adopted, there is no deterioration of the wire rodwhen the film is coated on the wire rod, but superior propertiessuitable for the wire rod, such as flexibility, adhesion, andworkability are recognized, which are preferable. Further, the film 18may be the same or different from the above-mentioned polyimide 16 whichcomprises the laminate film 10 of the present invention.

In addition, the adhesive laminate film for wire rod coating of thepresent invention may be, as shown in FIGS. 5 through 7, particularlyused for an accelerator. For example, as shown in FIG. 5(a), thepolyimide film 18 with a given width is wrapped around in the rim of asuper conductivity wire rod for accelerator 12 with its ends beingoverlapped. Besides, as shown in FIG. 5(b), the adhesive laminate film10 with a given width of the present invention is wrapped around in aspiral with the bonded layer 14 disposed outside and spaced at bothends. FIG. 6 shows its cross section. A plurality of coated wire rodsare subsequently heated to a predetermined temperature to bond betweenthe superconductivity wire rods via the bonded layer 14. The wire rodscoated with this adhesive laminate film for wire rod coating may be usedfor an accelerator in the embodiment as shown in FIG. 7.

The adhesive laminate film for wire rod coating according to the presentinvention have easy handling and workability by previously using aprepared laminate of the other polyimide film and an adhesive layer,which leads to an improvement of productivity.

Further, the adhesive film which comprises a thermoplastic polyimide anda thermosetting resin used as an adhesive layer in the present inventionmay be used as an insulating coating material, and the adhesive film mayalso be used in peeling off a sheet of released paper after wrapping aresin film which comprises a film-like thermoplastic polyimide and athermosetting resin and the released paper around the wire rod byoverlapping in twofold and, performing thermo compression bonding.

Furthermore, an adhesive film constructed by a thermoplastic resin and athermosetting resin, and a substance made by overlapping the otheravailable polyimide film such as Apical (manufactured by KanekaCorporation) are wrapped around the wire rod and directly crimped byheating to be coated.

The adhesive laminate film for wire rod coating according to the presentinvention has excellent workability at a low temperature, flexibility,and radiation resistance as well as a little deterioration of functionscaused by water adsorption and has few dielectric loss and furtherexcellent adhesion when the film is energized by coating the wire rod.More particularly, the thermoplastic polyimide used as a component of abonded layer in the present invention has a specific glass transitiontemperature within the range of 100° C. to 250° C. depending on thestructure, and melts by lamination at a temperature close to the glasstransition temperature so that the curing of the thermosetting resin maybe facilitated. Accordingly, after wrapping the laminate film of thepresent invention with its bonded layer inside around the wire rod, andthe like, the adhesive laminate film for wire rod coating is bonded tothe wire rod by heating at a glass transition temperature, that is, atthe temperature from 100° C. to 250° C. The wire rod, therefore, doesnot suffer deterioration due to few effects caused by heating. Further,compared to the conventional polyimide, the thermoplastic polyimide usedfor the bonded layer indicates a much lower water adsorption, so thatthe polyimide suffers less deterioration in functions caused by wateradsorption. Furthermore, when the wire rod is energized, due to a smalldielectric constant less than 3.2, it has less dielectric loss,therefore, it can control heating the wire rod. Besides, the polyimideis confirmed to have superior characteristics in radiation resistance.

These characteristics are suitable for coating of superconductivity wirerods and the like and favorably applied for the particular use forsuperconductivity magnets of accelerators, but the other uses are notparticularly limited. As described above, the embodiments of thepolyimide resin, and the resin composition, the film-state joiningcomponent, and the adhesive laminate film for wire rod coating accordingto the present invention have variously been described so far, but thepresent invention is not limited to these embodiments. Also, any and allmodifications, variations or equivalent arrangements which may occur tothose skilled in the art should be considered to be within the scope ofthe invention.

EXAMPLES

An explanation will be given in detail to the present invention byexamples mentioned below, but the present invention is not limited tothese examples.

Water absorption is calculated by measurement based on ASTM (AmericanSociety for Testing and Materials) D570. A film-like composition; acomposition sheet having a thickness of 25 μm, was heated at 150° C. for3 hours to obtain a cured composition sheet. W1 was weight of thecomposition sheet after having been cured which was obtained by furtherdrying at 150° C. for 30 minutes. W2 was weight obtained by wiping offthe surface of the sheet after having immersed into distilled water(under an atmosphere of 20° C., 60% RH) for 24 hours, and then the waterabsorption was calculated by the following formula:

Water absorption coefficient (%)=(W2−W1)/W1×100

Dielectric constant was calculated by making evaluations by the Q metermethod (1 kH₂) in accordance with JISC (Japanese Industrial StandardCommittee) 6481.

Peeling strength was measured in accordance with JISC 6481, describedbelow the conditions when a sample was in an ordinary state; at 20° C.,at a high temperature; at 150° C. The sample was cut in such a mannerthat the width of the obtained copper pattern of FCCL was 3 mm, and atensile test under the condition of peeling at the angle of 90 degreesat the peeling test speed of 50 mm/min was conducted using a tensiletester (“S-100-C” manufactured by Shimadzu Corporation). The measuredvalue is an average value of n=5.

The measuring method of materials in the examples 10 to 14 and thecomparative examples 8 to 9 is as follows:

Intrinsic Viscosity

Intrinsic viscosity of polyamic acid was measured at 30±1° C. with anOswald viscometer. The higher its intrinsic viscosity is, the higher itsdegree of polymerization is, which leads to superior mechanicalproperties as an end-product polyimide. Some concentrations of differentsolutions were determined to plot viscosity/concentration againstconcentration, and the line was extrapolated to zero concentration.

Glass Transition Temperature

The endothermic starting temperature was measured using a differentialscanning calorimeter (DSC220 manufactured by Seiko Instruments) underthe conditions of temperature rising velocity at 10° C./min. Thisendothermic starting temperature was regarded as a glass transitiontemperature. The lower the glass transition temperature is, the moresuperior the workability becomes.

Cross-cut Tape Test

A cross-cut tape test was carried out in accordance with JIS (JapaneseIndustrial Standards) K-5400. 10 points are the maximum and the higherthe points are, the more the composition sheet has excellent adhesion.

(d) Tensile Strength

A tensile strength was measured in accordance with JIS K-7172. Thehigher the value is, the more superior the mechanical strength becomes.

PCT treatment physical property measurements of Examples 15 to 27 andComparative Examples 10 to 19 were carried out as mentioned below.

The conditions of PCT (Pressure Cooker Test) treatment which was areliability test of materials for electronics were temperature 121° C.,humidity 100%, and 48 hours. The retention of peeling strength after PCTtreatment was calculated by the following formula when the peelingstrength before PCT treatment was represented as F₁, and the peelingstrength after PCT treatment was represented as F₂:

Retention (%) of peeling strength after PCT treatment=F₂/F₁×100

The residual volatile component in Examples 15 to 21 and ComparativeExamples 10 to 15 was measured by a gas chromatography. Measuringconditions were as follows:

(Measuring Conditions)

Equipment: Chem Station manufactured Hewlett Packard Japan, Ltd (HP).

Carrier gas: Helium

Column: HP-Wax Bonded Polyethylene Glycol manufactured by HP

Carrier flow rate: 45 ml/min

Detector: FID

The residual volatile component was calculated by the following formulawhen the weight of resin compound was represented as W₃, and theequivalent weight of the residual volatile component measured by the gaschromatography was represented by W₄:

Residual volatile component (Weight %)=W ₄/W ₃×100

Characteristic evaluation of a film-like laminated member in Examples 28to 30 and Comparative Examples 20 to 22 was performed as follows:

Residual Solvent Content

The measurement was carried out by the following procedure:

Put a sample film in a thermal decomposition device to change intovaporization by decomposing it.

Feed gas generated by the decomposition into a GC-MS column and thenstart measuring.

Compare the obtained peak area to the peak area of the calibration curbto calculate the amount of solvent.

Calculate the residual solvent content from the ratio by weight of thefilm decomposed as a sample and the weight of the calculated solvent.

The calibration curve was drawn by the following method:

Determine the peak area by injecting a solvent to be detected into theGC-MS.

Determine the peak area by carrying out similar measurements each timethe amount of the injected solvent was changed.

Plot the obtained result in a graph representing x-axis as the amount ofthe solvent and y-axis as the peak area.

Obtain a calibration curve based on the plot.

Assign the peak area obtained by measuring the GC-Ms after thermaldecomposition of the film, so that it makes the amount of the solventcontained in the film clarified.

Its measuring equipment and conditions are as follows:

Thermal decomposition device: JP-3 manufactured by Japan AnalyticalIndustry Co., Ltd.

GC: Hewlett Packard Hp5890-II

MS: Hewlett Packard Hp5871A

Decomposition conditions: 358° C.×5 sec

Column: DB-5 Capillary Column

Temperature profile: 35° C. (5 min)→temperature rise (10° C./min)

→150° C. (1.5 min)

Inlet/Detector: 250° C./280° C.

Oven/Needle temperature: 200° C./200° C.

Split ratio: 1/30

Sample amount: 0.5 mg

Peeling Strength

Peeling strength was measured by the following procedure at the timethat a laminated member and a copper foil were bonded:

Superimpose a film-like laminated member on a 18 μm-electrolytic copperfoil. Heat at 200° C. and apply a pressure of 3 MPa for 20 minutes toobtain a flexible copper clad laminate. The peeling strength of theobtained flexible copper clad laminate was measured in accordance withJIS C6481. Its conductor width was measured to be 3 mm.

The glass transition temperature measurements of Examples 35 to 42 andComparative Examples 29 to 33 were carried out as follows:

The glass transition temperature was calculated from dynamicvisco-elastic data using a DMS 200 (Japan Electronic IndustryDevelopment Association) in accordance with the DMA method.

Example 1

In a 500-ml glass flask, 0.1487 mole of3,3′-bis(amino-phenoxyphenyl)propane (meta-type, hereinafter referred toas BAPP-M) was added to 280 g of N,N-dimethylformamide (hereinafterreferred to as DMF) to be stirred and dissolved under a nitrogenatmosphere. The solution in the flask was further stirred while coolingwith iced water bath under a nitrogen substituted atmosphere. And then0.1487 mole of 2,2-bis(4-hydroxyphenyl)propane-dibenzoate-3,3′,4,4′-tetracarboxylic acid dianhydride(hereinafter referred to as ESDA) was gradually added with care to itsviscosity. When the viscosity reached 1500 poise, the addition of ESDAwas stopped and a polyamic acid polymer solution was obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued below 100° C. for an hour to be imidized. Then,this solution was added dropwise to methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thencleaning was performed with methanol After drying at 100° C. for 2hours, a polyimide powder was obtained.

20 g of the obtained polyimide powder, 5 g of epoxy resin of BisphenolA; Epikote 828 (manufactured by Shell International ChemicalsCorporation), and 0.015 g of 2-ethyl-4-methylimidazole as an acceleratorwere dissolved in 83 g of DMF. The obtained varnish was cast onto aglass plate, dried at 100° C. for 10 minutes, peeled off from the glassplate and set on a steel frame. A sheet having a thickness of 25 μm wasobtained by further drying at 150° C. for 20 minutes. The obtained sheetwas sandwiched between a polyimide film (Apical 50AH, manufactured byKaneka Corporation) and a copper foil of 25 μm thickness, and then washeated at 200° C. and pressurized at pressure 3 MPa for 20 minutes toobtain a flexible copper clad laminate.

Example 2

The varnish obtained in Example 1 was applied onto a polyimide film(Apical 50AH manufactured by Kaneka Corporation) and then dried byheating at 100° C. for 10 minutes and further dried by heating at 150°C. for 20 minutes to form an adhesive layer having a thickness of 25 μm.The obtained one-sided polyimide film and a copper foil having athickness of 25 μm were heated at 200° C. and pressurized at pressure 3MPa for 20 minutes to obtain a flexible copper clad laminate.

Example 3

20 g of the polyimide powder obtained in Example 1 and 5 g of glycidylamine-type epoxy resin; TETRAD-C (manufactured by Mitsubishi GasChemical Co., Inc.) were dissolved in 83 g of DMF to prepare a varnish.The obtained varnish was cast onto a glass plate, dried at 100° C. for10 minutes, peeled off from the glass plate, set on a steel frame andfurther dried at 150° C. for 20 minutes. Then a sheet having a thicknessof 25 μm was obtained. The obtained sheet was sandwiched between apolyimide film (Apical 50AH, Kaneka Corporation) and a copper foil of 25μm thickness. After heating at 200° C. and applying a pressure of 3 MPafor 20 minutes, a flexible copper clad laminate was obtained.

Example 4

A polyamic acid polymer solution and a polyimide powder were obtained inthe same manner as in Example 1 except that a diamine component was4,4′-(1,3-phenylenebis (1-methyl ethylidene)) bisaniline (para-type).

The obtained polyimide powder was treated in the same manner as inExample 1 to obtain a flexible copper clad laminate.

Example 5

A polyamic acid polymer solution and a polyimide powder were obtained inthe same manner as in Example 1 except that a diamine component was4,4′-bis(aminophenoxyphenyl)propane (para-type).

The obtained polylmide powder was treated in the same manner as inExample 1 to obtain a flexible copper clad laminate.

Example 6

A polyamic acid polymer solution; and a polyimide powder were obtainedin the same manner as in Example 1 except that a diamine component was3,3′-bis(aminophenoxyphenyl)sulfone (BAPS-M).

The obtained polyimide powder was treated in the same manner as inExample 1 to obtain a flexible copper clad laminate.

Comparative Example 1

In a 500-ml glass flask, 0.1487 mole of3,3′-bis(amino-phenoxyphenyl)propane (hereinafter referred to as BAPP-M)was added to 280 g of dimethylformamide (DMF) to be stirred anddissolved under a nitrogen atmosphere. The solution in the flask wasfurther stirred while cooled with an ice-water bath under a nitrogensubstituted atmosphere. And then 0.1487 mole ofbenzophenonetetracarboxylic acid dianhydride (hereinafter referred to asBTDA) was gradually added with care to its viscosity. When the viscosityreached 1500 poise, the addition of BTDA was stopped and a polyamic acidpolymer solution was obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued below 100° C. for an hour for imidization. Then,this solution was added dropwise into methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thenSoxhlet cleaning was performed with methanol. After drying at 100° C.for 2 hours, a polyimide powder was obtained. 20 g of the obtainedpolyimide powder, 5 g of Epikote 828 (manufactured by ShellInternational Chemicals Corporation), and 0.015 g of2-ethyl-4-methylimidazole were dissolved in 83 g of DMF to prepare avarnish. The obtained varnish was cast onto a glass plate, and peeledoff from the glass plate, after dried at 100° C. for 10 minutes and seton a steel frame. A sheet having a thickness of 25 μm was obtained byfurther drying at 150° C. for 20 minutes. The obtained sheet wassandwiched between a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and then was heatedat 200° C. and pressurized at pressure 3 MPa for 20 minutes to obtain aflexible copper clad laminate.

Comparative Example 2

20 g of the polyimide powder obtained in Example 1 was dissolved in 83 gof DMF to prepare a varnish. The obtained varnish was cast onto a glassplate, dried at 100° C. for 10 minutes, peeled off from the glass plate,and set on a steel frame. A sheet having a thickness of 25 μm wasobtained by further drying at 150° C. for 20 minutes. The obtained sheetwas sandwiched between a polyimide film (Apical 50AH, manufactured byKaneka Corporation) and a copper foil of 25 μm thickness, and then washeated at 200° C. and pressurized at pressure 3 MPa for 20 minutes toobtain a flexible copper clad laminate.

Comparative Example 3

10 g of Pratabond (Co-polymerized nylon, manufactured by Nihon RilsanCo., Ltd.), 20 g of Epikote 828 (manufactured by shell InternationalChemicals Corporation), and 1 g of diaminodiphenyl sulfone weredissolved in 83 g of DMF to prepare a varnish. The obtained varnish wascast onto a glass plate, dried at 100° C. for 10 minutes, peeled offfrom the glass plate and set on a steel frame. A sheet having athickness of 25 μm was obtained by further drying at 150° C. for 20minutes. The obtained sheet was sandwiched between a polyimide film(Apical 50AH, manufactured by Kaneka Corporation) and a copper foil of25 μm thickness, and then was heated at 200° C. and pressurized atpressure 3 MPa for 20 minutes to obtain a flexible copper clad laminate.

Peeling strength and solder heat resistance were evaluated on thecoppered flexible laminated plate obtained in each of Examples 1 to 6and Comparative Examples 1 to 3 as described above. Water absorption ofeach adhesive sheet was evaluated as well. The results obtained areshown in Table 1.

TABLE 1 Peeling strength (kgf/cm) Solder heat Water 20° C. 150° C.resistance absorption (%) Example 1 1.0 0.8 ◯ 0.5 Example 2 1.0 0.8 ◯0.5 Example 3 1.2 0.9 ◯ 0.6 Example 4 1.1 0.9 ◯ 0.6 Example 5 1.0 0.8 ◯0.6 Example 6 1.0 0.8 ◯ 1.0 Comparative 1.0 0.8 X 1.8 Example 1Comparative 0.2 0.1 ◯ 0.4 Example 2 Comparative 1.2 0.1 X 2.0 Example 3

Example 7

In a 500 ml glass flask, 0.1338 mole of3,3′-bis(amino-phenoxyphenyl)propane (meta-type, hereinafter referred toas BAPP-M) and 0.01487 mole of α,{overscore (ω)}-bis (3-aminopropyl)polydimethylsiloxane (APPS) were added to 280 g of dimethyl-formamide(hereinafter referred to as DMF) to be stirred and dissolved under anitrogen atmosphere. The solution in the flask was further stirred whilecooled with an ice-water bath under a nitrogen substituted atmosphere.And then 0.1487 mole of 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylic acid dianhydride (hereinafter referred to asESDA) was gradually added with care to its viscosity. When the viscosityreached 1000 poise, the addition of ESDA was stopped and then a polyamicacid polymer solution was obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued below 100° C. for an hour for imidization. Then,this solution was added dropwise into methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thenSoxhlet cleaning was performed with methanol. After drying at 100° C.for 2 hours, a polyimide powder was obtained. 20 g of the obtainedpolyimide powder, 5 g of epoxy resin of Bisphenol A; Epikote 828(manufactured by Shell International Chemicals Corporation), and 0.015 gof 2-ethyl-4-methylimidazole were dissolved in 83 g of DMF and mixed toobtain a varnish. The obtained varnish was cast onto a glass plate,dried at 100° C. for 10 minutes, peeled off from the glass plate and seton a steel frame. A sheet having a thickness of 25 μm was obtained byfurther drying at 150° C. for 20 minutes. The obtained sheet wassandwiched between a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and then was heatedat 200° C. and pressurized at pressure 3 MPa for 20 minutes to obtain aflexible copper clad laminate.

Example 8

The varnish obtained in Example 7 was applied onto a polyimide film(Apical 50AH manufacture by Kaneka Corporation) and then dried byheating at 100° C. for 10 minutes and further dried by heating at 150°C. for 20 minutes to form an adhesive layer having a thickness of 25 μm.The obtained one-sided polyimide film and a copper foil of 25 μmthickness were heated at 200° C. and pressurized at pressure 3 MPa for20 minutes to obtain a flexible copper clad laminate.

Example 9

20 g of the polyimide powder obtained in Example 7 and 5 g of glycidylamine-type epoxy resin; TETRAD-C (manufactured by Mitsubishi GasChemical Co., Inc.) were dissolved in 83 g tetrahydrofuran (hereinafterreferred to as THF) to prepare a varnish. The obtained varnish was castonto a glass plate. After drying at 100° C. for 10 minutes, the varnishwas peeled off from the glass plate, set on a steel frame, and furtherdried at 150° C. for 20 minutes to obtain a sheet having a thickness of25 μm. The obtained sheet was sandwiched between a polyimide film(Apical 50AH, manufactured by Kaneka Corporation) and a copper foil of25 μm thickness. After heating at 200° C. and applying a pressure of 3MPa for 20 minutes, a flexible copper clad laminate was obtained.

Comparative Example 4

In a 500 ml glass flask, 0.1487 mole of BAPP-M was added to 280 g ofdimethylformamide (DMF) to be stirred and dissolved under a nitrogenatmosphere. The solution in the flask was further stirred while cooledwith an ice-water bath under a nitrogen substituted atmosphere. And then0.1487 mole of benzophenonetetracarboxylic acid dianhydride (hereinafterreferred to as BTDA) was gradually added with care to its viscosity.When the viscosity reached 1000 poise, the addition of BTDA was stoppedand then a polyamic acid polymer solution was obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride ,ere added. After stirring for an hour, stirringwas further continued below 100° C. for an hour for imidization. Then,this solution was added dropwise into methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thenSoxhlet cleaning was performed with methanol. After drying at 100° C.for 2 hours, a polyimide powder was obtained.

20 g of the obtained polyimide powder, 5 g of Epikote 828 (manufacturedby Shell International Chemicals Corporation), and 0.015 g of2-ethyl-4-methylimidazole were dissolved in 83 g of THF and mixed toobtain a varnish. The vanished was cast onto a glass plate, dried at100° C. for 10 minutes, peeled off from the glass plate and set on asteel frame. A sheet having a thickness of 25 μm was obtained by furtherdrying at 150° C. for 20 minutes. The obtained sheet was sandwichedbetween a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and then was heatedat 200° C. and pressurized at pressure 3 MPa for 20 minutes to obtain aflexible copper clad laminate.

Comparative Example 5

In a 500 ml glass flask, 0.1487 mole of3,3′-bis(amino-phenoxyphenyl)propane (hereinafter referred to as BAPP-M)was charged into 280 g of dimethylformamide (DMF) to be stirred anddissolved under a nitrogen atmosphere. The solution in the flask wasfurther stirred while cooled with an ice-water bath under a nitrogensubstituted atmosphere. And then 0.1487 mole of pyromellitic aciddianhydride was gradually added with care to its viscosity. When theviscosity reached 1000 poise, the addition of pyromellitic aciddianhydride was stopped and then a polyamic acid polymer solution wasobtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued below 100° C. for an hour for imidization. Then,this solution was added dropwise into methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thenSoxhlet cleaning was performed with methanol. After drying at 100° C.for 2 hours, a polyimide powder was obtained.

The trial of dissolving 20 g of obtained polyimide powder in 83 g of THFwas failed because of precipitation of the polyimide powder.

Comparative Example 6

20 g of the polyimide powder obtained in Example 7 was dissolved in 83 gof THF to prepare a varnish. The obtained varnish was cast onto a glassplate, dried at 100° C. for 10 minutes, peeled off from the glass plateand set on a steel frame, and further dried at 150° C. for 20 minutes. Asheet having a thickness of 25 μm was obtained. The obtained sheet wassandwiched between a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness. After heating at 200°C. and applying a pressure of 3 MPa for 20 minutes, a flexible copperclad laminate was obtained.

Comparative Example 7

10 g of Pratabond M1276 (Co-polymerized nylon, manufactured by NihonRilsan Co., Ltd.), 20 g of Epikote 828 (manufactured by ShellInternational Chemicals Corporation), and 1 g of diaminodiphenyl sulfonewere dissolved in 83 g of DMF to obtain a varnish. The obtained varnishwas cast onto a glass plate, dried at 100° C. for 10 minutes peeled offfrom the glass plate and set on a steel frame. A sheet having athickness of 25 μm was obtained by further drying at 150° C. for 20minutes. The obtained sheet was sandwiched between a polyimide film(Apical 50AH, manufactured by Kaneka Corporation) and a copper foil of25 μm thickness, and then was heated at 200° C. and pressurized atpressure 3 MPa for 20 minutes to obtain a flexible copper clad laminate.

Peeling strength and solder heat resistance were evaluated on theflexible laminated plate obtained in each of Examples 7 to 9 andComparative Examples 4 to 7. Water absorption of each adhesive sheet wasevaluated as well. The results obtained are shown in Table 2.

TABLE 2 Peeling strength Water (kgf/cm) Solder heat Absorption THF 20°C. 150° C. resistance (%) solubility Example 7 1.0 0.7 ◯ 0.5 ◯ Example 81.0 0.7 ◯ 0.5 ◯ Example 9 1.2 0.8 ◯ 0.6 ◯ Comparative Example 4 1.0 0.7X 1.8 ◯ Comparative Example 5 — — — — X Comparative Example 6 0.2 0.1 ◯0.4 ◯ Comparative Example 7 1.2 0.1 X 2.0 ◯

Example 10

In a 500 ml glass flask with a reflux condenser, 300 g of aceticanhydride and 50 g of crude material of tetracarboxylic acid dianhydride(ESDA) were added. After stirring was conducted by heating at 120° C.for an hour, the temperature was lowered to separate the recrystallizedESDA by filtration. ESDA having 1% of lower impurities was obtainedafter drying in a vacuum at 120° C. for 24 hours.

20.0 g (100 mmole) of 4,4′-diaminodiphenyl ether (DDE) and 244 g ofdimethylformamide (DMF) were added to a 500 ml four-necked flaskequipped with a thermometer, a stirrer, and a calcium chloride tube.After dissolving diamine, 2,2-bis4-hydroxyphenyl)propanedibenzoate-3,3′,4,4-tetracarboxylic aciddianhydride (ESDA) having 0.3% by weight of residual impurities content,57.7 g (100 mole of pure ESDA were added to the flask at 25° C. Afterstirring for 3 hours, the solution was reacted to obtain a polyamic acidsolution. The intrinsic viscosity of this polyamic acid solution was1.1.

The polyamic acid solution was applied by flow casting onto a PET filmand heated at 80° C. for 30 minutes. After peeling off the PET film,heating was conducted at 150° C. 200° C., and 250 ° C. for 30 minutesrespectively. After f heating at 300° C. for 10 minutes, a polyimidefilm of high strength having a thickness of 25 μm was obtained. It wasconfirmed that there was absorption by an imide group at 1780 cm⁻¹ in aninfrared radiation measurement. The polyimide film had a glasstransition temperature of 225° C. and a tensile strength of 15.3

Further, the polyamic acid solution was cast onto an aluminum plate (JISH4000 A1050P) and al soft soda glass plate with a doctor knife. Afterheating at 80° C., 150° C., 200° C., and 250° C. respectively for 30minutes, heating was finally conducted at 300° C. for 10 minutes toobtain a polyimide coating having a thickness of 20 to 25 μm. In acrosscut tape test, both of the polyimide coatings on the aluminum andglass plates got 10 points.

Example 11

A polyamic acid with an intrinsic viscosity of 1.1 was obtained in thesimilar manner as in Example 10 except that the adding order of ESDAhaving a residual impurities content of 0.3 weight % and DDE wasreversed. This polyimide resin was confirmed to have absorption causedby an imide group at 1780 cm⁻¹ in an infrared radiation measurement. Thepolyimide film had a glass transition temperature of 225° C. and atensile strength of 15.2 kg/cm². On the other hand, in a crosscut tapetest, both of the polyimide coating on the aluminum and glass plates got10 points.

Example 12

A polyamic acid solution with an intrinsic viscosity of 1.0 was obtainedin the similar manner as in Example 10 except that diamine was used as19.8 g of 4,4′-diaminodiphenylmethane (DAM) instead of DDE. In addition,a polyimide film and a polyimide coating with high strength wereobtained in the same manner as in Example 10. This polyimide resin wasconfirmed to have absorption caused by an imide group at 1780 cm⁻¹ in aninfrared radiation measurement. The polyimide film had a glasstransition temperature of 220° C. and a tensile strength of 15.2 kg/cm².On the other hand, in a crosscut tape test, both of the polyimidecoating on the aluminum and glass plates got 10 points.

Example 13

A polyamic acid solution with an intrinsic viscosity of 1.0 was obtainedin the similar manner as in Example 10 except that diamine was used as2,2-bis [4-(4-aminophenoxy)phenyl] propane (BAPP) instead of DDE. Inaddition, a polyimide film and a polyimide coating with high strengthwere obtained in the same manner as in Example 10. This polyimide wasconfirmed to have absorption caused by an imide group at 1780 cm⁻¹ in aninfrared radiation measurement. The polyimide film had a glasstransition temperature of 205° C. and a tensile strength of 14.5 kg/cm².On the other hand, in a crosscut tape test, both of the polyimidecoating on the aluminum and glass plates got 10 points.

Example 14

A polyamic acid with an intrinsic viscosity of 0.8 was obtained in thesimilar manner as in Example 10 except that 57.7 g (100 mmole in ESDApure content) of ESDA wit residual impurities content of 1.0 wt % as anacid dianhydride component. In addition, a polyimide film and apolyimide coating with high strength were obtained in the same manner asin Example 10. This polyimide resin was confirmed to lave absorptioncaused by an imide group at 1780 cm⁻¹ in an infrared radiationmeasurement. The polyimide film had a glass transition temperature of215° C. and a tensile strength of 12.5 kg/cm². On the other hand, in acrosscut tape test, both of the polyimide coating on the aluminum andglass plates got 10 points.

Comparative Example 8

A polyamic acid with an intrinsic viscosity of 0.24 was obtained in thesimilar manner as in Example 10 except that 57.7 g (100 mmole in ESDApure content) of ESDA with compound (1) of 1.5 wt % as an aciddianhydride component. In addition, a polyimide film and a polyimidecoating with high strength were obtained in the same manner as inExample 10. This polyimide resin was confirmed to have absorption causedby an imide group at 1780 cm⁻¹ in an infrared radiation measurement. Thepolyimide film was very fragile and not self-support. Accordingly, itwas impossible to measure its tensile strength. In a crosscut tape test,both of the polyimide coating on the aluminum and glass plates got 2points.

Comparative Example 9

A polyamic acid with an intrinsic viscosity of 0.28 was obtained in thesimilar manner as in Example 10 except that 57.7 g (100 mmole in ESDApure content) of ESDA with compound (2) of 1.5 wt % as an aciddianhydride component. In addition, a polyimide film and a polyimidecoating with high strength were obtained in the same manner as inExample 10. This polyimide resin was confirmed to have absorption causedby an imide group at 1780 cm⁻¹ in an infrared radiation measurement. Thepolyimide film was very fragile and not self-support. Accordingly, itwas impossible to measure its tensile strength. In a crosscut tape test,both of the polyimide coating on the aluminum and glass plates got 3points.

Example 15

In a 500 ml glass flask, 0.1487 mole of3,3′-bis(amino-phenoxyphenyl)propane (meta-type: hereinafter referred toas BAPP-M) was added to 280 g of dimethylformamide (hereinafter referredto as DMF) to be stirred and dissolved under a nitrogen atmosphere. Thesolution in the flask was further stirred while cooled with an ice-waterbath under a nitrogen substituted atmosphere. And then 0.1487 mole of2,2-bis(4-hydroxyphenyl) propanedibenzoate-3,3′,4,4′-tetracarboxylicacid dianhydride (hereinafter referred to as ESDA) was gradually withcare to its viscosity. When the viscosity reached 1500 poise, theaddition of ESDA was stopped and then a polyamic acid polymer solutionwas obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued below 100° C. for an hour for imidization. Then,this solution was added dropwise into methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thenSoxhlet cleaning was performed with methanol. After drying at 100° C.for 2 hours, a polyimide powder was obtained.

20 g of the obtained polyimide powder, 5 g of epoxy resin of BisphenolA; Epikote 828 (manufactured by Shell International ChemicalsCorporation), and 0.015 g of 2-ethyl-4-methylimidazole were dissolved in83 g of mixed solution of dioxane and THF at a 1:1 weight ratio toprepare a varnish. The obtained varnish was cast onto a glass plate,dried at 100° C. for 10 minutes, peeled off from the glass plate and seton a steel frame. A sheet having a thickness of 25 μm was obtained byfurther drying at 150° C. for 20 minutes. The obtained sheet wassandwiched between a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and then was heatedat 200° C. and pressurized at pressure 3 MPa for 20 minutes to obtain aflexible copper clad laminate.

Example 16

The varnish obtained in Example 15 was applied onto a polyimide film(Apical 50AH manufactured by Kaneka Corporation) and then dried byheating at 100° C. for 10 minutes and further dried by heating at 150°C. for 20 minutes to form an adhesive layer having a thickness of 25 μm.The obtained one-sided polyimide film and a copper foil of 25 μmthickness were heated at 200° C. and pressurized at pressure 3 MPa for20 minutes to obtain a flexible copper clad laminate.

Example 17

20 g of the polyimide powder obtained in Example 15 and g ofglycidylamine-type epoxy resin; TETRAD-C (manufactured by MitsubishiChemical Co., Inc.) were dissolved in 83 g of mixed solution of dioxaneand THF at a 1:1 weight ratio to obtain a varnish. The obtained varnishwas cast onto a glass plate, dried at 100° C. for 10 minutes, peeled offfrom the glass plate and set on a steel frame. A sheet having athickness of 25 μm was obtained by further drying at 150° C. for 20minutes. The obtained sheet was sandwiched between a polyimide film(Apical 50AH, manufactured by Kaneka Corporation) and a copper foil of25 μm thickness, and then was heated at 200° C. and pressurized atpressure 3 MPa for 20 minutes to obtain a flexible copper clad laminate.

Example 18

A polyamic acid polymer solution and a polyimide powder were obtained inthe same manner as in Example 15 except that diamine component was4,4′-[1,3-phenylenebis(1-methyl ethylidene)] bisaniline (para-type). Theobtained polyimide powder was treated in the same manner as in Example15 to obtain a flexible copper clad laminate.

Example 19

A polyamic acid polymer solution land a polyimide powder were obtainedin the same manner as in Example 15 except that a diamine component was4,4′-bis(aminophenoxyphenyl) propane (para-type). The obtained polyimidepowder was treated in the same manner as in Example 15 to obtain aflexible copper clad laminate.

Example 20

A polyamic acid polymer solution and a polyimide powder were obtained inthe same manner as in Example 15 except that a diamine component was3,3′-bis(aminophenoxyphenyl) sulfone (BAPS-M). The obtained polyimidepowder was treated in the same manner as in Example 15 to obtain aflexible copper clad laminate.

Example 21

A flexible copper clad laminate was obtained in the same manner as inExample 15 except that the polyimide powder obtained in Example 15,Bisphenol A-type epoxy resin (Epikote 828), and2-ethyl-4-methylimidazole used as a curing accelerator were dissolved inDMF.

Comparative Example 10

In a 500 ml glass flask, 0.1487 mole of3,3′-bis(amino-phenoxyphenyl)propane (hereinafter referred to as BAPP-M)was added to 280 g of dimethylformamide (DMF) to be stirred anddissolved under a nitrogen atmosphere. The solution in the flask wasfurther stirred while cooled with an ice-water bath under a nitrogensubstituted atmosphere. And then 0.1487 mole ofbenzophenonetetracarboxylic acid dianhydride (hereinafter referred to asBTDA) was gradually addled while with care to its viscosity. When theviscosity reached 1500 poise, the addition of BTDA was stopped and thena polyamic acid polymer solution was obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued below 100° C. for an hour for imidization. Then,this solution was added dropwise into methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thenSoxhlet cleaning was performed with methanol. After drying at 100° C.for 2 hours, a polyimide powder was obtained.

20 g of the obtained polyimide power, 5 g of Epikote 828 (manufacturedby Shell International chemicals Corporation), and 0.015 g of2-ethyl-4-methylimidazole were dissolved in 83 g of DMF to obtain avarnish. The obtained varnish was cast onto a glass plate, dried at 100°C. for 10 minutes, peeled off from the glass plate and set on a steelframe. A sheet having a thickness of 25 μm was obtained by furtherdrying at 150° C. for 20 minutes. The obtained sheet was sandwichedbetween a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and then was heatedat 200° C. and pressurized at pressure 3 MPa for 20 minutes to obtain aflexible copper clad laminate.

Comparative Example 11

A flexible copper clad laminate was obtained in the same manner as inComparative Example 10 except that the polyimide powder obtained inComparative Example 10 was dissolved in a mixed solution of dioxane andTBF at a 1:1 weight ratio.

Comparative Example 12

20 g of the polyimide powder obtained in Example 15 was dissolved in 83g of DMF to prepare a varnish. The obtained varnish was cast onto aglass plate, dried at 100° C. for 10 minutes, peeled off from the glassplate and set on a steel frame. A sheet having a thickness of 25 μm wasobtained by further drying at 150° C. for 20 minutes. The obtained sheetwas sandwiched between a polyimide film (Apical 50AH, manufactured byKaneka Corporation) and a copper foil of 25 μm thickness. After heatingat 200° C. and applying a pressure of 3 MPa for 20 minutes, a flexiblecopper clad laminate was obtained.

Comparative Example 13

A flexible copper clad laminate was obtained in the same manner as inComparative Example 12 except that the polyimide powder obtained inExample 15 was dissolved in a mixed solution of dioxane and THF at a 1:1weight ratio.

Comparative Example 14

10 g of Pratabond M1276 (Co-polymerized nylon, manufactured by NihonRilsan Co., Ltd.), 20 g of Epikote 828 (manufactured by ShellInternational Chemicals Corporation), and 1 g of diaminodiphenyl sulfonewere dissolved in 83 g of DMF to obtain a varnish. The obtained varnishwas cast onto a glass plate, dried at 100° C. for 10 minutes, peeled offfrom the glass plate and set on a steel frame. A sheet having athickness of 25 μm was obtained by further drying at 150° C. for 20minutes. The obtained sheet was sandwiched between a polyimide film(Apical 50AH, manufactured by Kaneka Corporation) and a copper foil of25 μm thickness, and then was heated at 200° C. and pressurized atpressure 3 MPa for 20 minutes to obtain a flexible copper clad laminate.

Comparative Example 15

A flexible copper clad laminate was obtained in the same manner as inComparative Example 5 except that Pratabond M1276, Epikote 828, anddiaminodiphenyl sulfone in Comparative Example 15 were dissolved in amixed solution of dioxane and THF at a 1:1 weight ratio.

Water absorption and residual volatile component were evaluated on theresin composition, and peeling strength and solder heat resistance wereevaluated on the flexible copper clad laminate obtained in each ofExamples 15 to 21 and Comparative Examples 10 to 15. The waterabsorption for each adhesive sheet was evaluated as well. The resultsobtained are shown in Table 3.

TABLE 3 Peeling strength Peeling strength Peeling strength Residual(kgf/cm) (kgf/cm) retention (%) after Water volatile (Before PCTtreatment) (After PCT treatment) PCT treatment Solder heat absorptioncontent 20° C. 150° C. 20° C. 150° C. 20° C. 150° C. resistance (%) (%by weight) Example 15 1.0 0.8 0.9 0.7 90 88 ◯ 0.5 0.3 Example 16 1.0 0.80.9 0.7 90 88 ◯ 0.5 0.2 Example 17 1.2 0.9 1.1 0.8 92 89 ◯ 0.6 0.5Example 18 1.1 0.9 1.0 0.8 91 89 ◯ 0.6 0.5 Example 19 1.0 0.8 0.9 0.7 9088 ◯ 0.6 0.5 Example 20 1.0 0.8 0.9 0.7 90 88 ◯ 1.0 0.7 Example 21 1.00.8 0.5 0.4 50 50 ◯ 0.5 1.5 Comparative Example 10 1.0 0.8 0.2 0.1 20 13X 1.8 5.0 Comparative Example 11 1.0 0.8 0.3 0.2 30 25 X 1.8 3.5Comparative Example 12 0.2 0.1 0.0 0.0 0 0 ◯ 0.4 0.5 Comparative Example13 0.2 0.1 0.0 0.0 0 0 ◯ 0.4 0.3 Comparative Example 14 1.2 0.1 0.2 0.017 0 X 2.0 4.8 Comparative Example 15 1.2 0.1 0.3 0.0 25 0 X 2.0 3.7

Example 22

In a 500 ml glass flask, 0.1487 mole of 3,3′-bis (amino-phenoxyphenyl)propane (meta-type: hereinafter referred to as BAPP-M) was added to 280g of dimethylformamide (hereinafter referred to as DMF) to be stirredand dissolved under a nitrogen atmosphere. The solution in the flask wasfurther stirred while cooled with an ice-water bath under a nitrogensubstituted atmosphere. And then 0.1416 mole of 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylic acid dianhydride(hereinafter referred to as ESDA) was gradually added with care to itsviscosity. When the viscosity reached 1500 poise, the addition of ESDAwas stopped and then a polyamic acid oligomer solution was obtained.

To this polyamic acid oligomer solution, 150 g of DMF, 35 g ofβ-picoline, and 60 g of acetic anhydride were added. After stirring foran hour, stirring was further continued below 100° C. for an hour forimidization. Then, this solution was added dropwise into methanol withvigorous stirring. After drying filamentous polyimide precipitated outof the methanol at 100° C. for 30 minutes, the polyimide was pulverizedby a mixer and then Soxhlet cleaning was performed with methanol. Afterdrying at 100° C. for 2 hours, a polyimide oligomer powder was obtained(molecular weight 30000).

20 g of the obtained polyimide oligomer powder, 5 g of epoxy resin ofBisphenol A; Epikote 828 (manufactured by Shell International ChemicalsCorporation), and 0.015 g of 2-ethyl-4-methylimidazole as a curingaccelerator were dissolved in 83 g of DMF to obtain a varnish. Theobtained varnish was cast onto a glass plate, dried at 100° C. for 10minutes, peeled off from the glass plate and set on a steel fame. Asheet having a thickness of 25 μm was obtained by further drying at 150°C. for 20 minutes. The obtained sheet was sandwiched between a polyimidefilm (Apical 50AH, manufactured by Kaneka Corporation) and a copper foilof 25 μm thickness, and then was heated at 200° C. and pressurized atpressure 3 MPa for 20 minutes to obtain a flexible copper clad laminate.

Example 23

The varnish obtained in Example 22 was applied onto a polyimide film(Apical 50AH, manufactured by Kaneka Corporation). After drying byheating at 100° C. for 10 minutes, the varnish was further dried byheating at 150° C. for 20 minutes to form an adhesive layer having athickness of 25 μm. A single-sided polyimide film with the obtainedadhesive layer and a copper foil of 25 μm thickness were heated at 200°C. under the pressure of 3 MPa for 20 minutes to obtain a flexiblecopper clad laminate.

Example 24

20 g of the polyimide powder obtained in Example 22 and 5 g ofglycidylamine-type epoxy resin; TETRAD-C (manufactured by Mitsubishi GasChemical Co., Inc.) were dissolved in 83 g of DMF to obtain a varnish.The obtained varnish was cast onto a glass plate, dried at 100° C. for10 minutes, peeled off from the glass plate and set on a steel frame. Asheet having a thickness of 25 μm was obtained by further drying at 150°C. for 20 minutes. The obtained sheet was sandwiched between a polyimidefilm (Apical 50AH, manufactured by Kaneka Corporation) and a copper foilof 25 μm thickness, and then was heated at 200° C. and pressurized atpressure 3 MPa for 20 minutes to obtain a flexible copper clad laminate.

Example 25

A polyamic acid oligomer solution and a polyimide oligomer powder(molecular weight: 40000) were obtained in the same manner as in Example22 except that a diamine component was4,4′-[1,3-phenylenebis(1-methylethylidene)] bisaniline (para-type).

The obtained polyimide oligomer powder was treated in the same manner asin Example 22 to obtain a flexible copper clad laminate.

Example 26

A polyamic acid oligomer solution and a polyimide oligomer powder(molecular weight: 20000) were obtained in the same manner as in Example22 except that a diamine component was4,4′-bis(aminophenoxyphenyl)propane (para-type).

The obtained polyimide oligomer powder was treated in the same manner asin Example 22 to obtain a flexible copper clad laminate.

Example 27

A polyamic acid oligomer solution and a polyimide oligomer powder(molecular weight: 10000) were obtained in the same manner as in Example22 except that a diamine component was3,3′-bis(aminophenoxyphenyl)sulfone (BAPS-M). The thus-obtainedpolyimide oligomer powder was treated in the same manner as in Example22 to obtain a flexible copper clad laminate.

Comparative Example 16

In a 500 ml glass flask, 0.1487 mole of 3,3′-bis(amino-phenoxyphenyl)propane (hereinafter referred to as BAPP-M) was added to 280 g ofdimethylformamide (DMF) to be stirred and dissolved under a nitrogenatmosphere. The solution in the flask was further stirred while cooledwith an ice-water bath under a nitrogen substituted atmosphere. And then0.1416 mole of benzophenonetetracarboxylic acid dianhydride (hereinafterreferred to as BTDA) was gradually added with care to its viscosity.When the viscosity reached 1500 poise, the addition of BTDA was stoppedand then a polyamic acid oligomer solution was obtained.

To this polyamic acid oligomer solution, 150 g of DMF, 35 g ofβ-picoline, and 60 g of acetic anhydride were added. After stirring foran hour, stirring was further continued below 100° C. for an hour forimidization. Then, this solution was added dropwise into methanol withvigorous stirring. After drying filamentous polyimide oligomerprecipitated out of the methanol at 100° C. for 30 minutes, thepolyimide oligomer was pulverized by a mixer and then Soxhlet cleaningwas performed with methanol. After drying at 100° C. for 2 hours, apolyimide powder was obtained (molecular weight: 30000).

20 g of the obtained polyimide oligomer powder, 5 g of Epikote 828(manufactured by Shell International Chemicals Corporation), and 0.015 gof 2-ethyl-4-methylimidazole were dissolved in 83 g of DMF to obtain avarnish. The obtained varnish was cast onto a glass plate. After dryingat 100° C. for 10 minutes, the varnish was peeled off from the glassplate and was set on an iron frame. A sheet having a thickness of 25 μmwas obtained by further drying at 150° C. for 20 minutes. The obtainedsheet was sandwiched between a polyimide film (Apical 50AH, manufacturedby Kaneka Corporation) and a copper foil of 25 μm thickness, and thenwas heated at 200° C. and pressurized at pressure 3 MPa for 20 minutesto obtain a flexible copper clad laminate.

Comparative Example 17

20 g of the polyimide oligomer powder obtained in Example 22 wasdissolved in 83 g of DMF to obtain a varnish. The obtained varnish wascast onto a glass plate. After drying at 100° C. for 10 minutes, thevarnish was peeled off from the glass plate and was set on a steelframe. A sheet having a thickness of 25 μm in was obtained by furtherdrying at 150° C. for 20 minutes. The obtained sheet was sandwichedbetween a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness. After heating at 200°C. and applying a pressure of 3 MPa for 20 minutes, a flexible copperclad laminate was obtained.

Comparative Example 18

10 g of Pratabond M1276 (Co-polymerized nylon, manufactured by NihonRilsan Co., Ltd.), 20 g of Epikote 828 (manufactured by ShellInternational Chemicals Corporation), and 1 g of diaminodiphenyl sulfonewere dissolved in 83 g of DMF to obtain a varnish. The obtained varnishwas cast onto a glass plate. After drying at 100° C. for 10 minutes, thevarnish was peeled off from the glass plate and was set on a steelframe. A sheet having a thickness of 25 μm was obtained by furtherdrying at 150° C. for 20 minutes. The obtained sheet was sandwichedbetween a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and then was heatedat 200° C. and pressurized at pressure 3 MPa for 20 minutes to obtain aflexible copper clad laminate.

Comparative Example 19

A flexible copper clad laminate was obtained in the same manner as inExample 22 except that a polyimide polymer powder (molecular weight:100000) was obtained by gradually adding 0.1487 mole of ESDA which isequivalent mole to 0.1487 mole of BAPP-M in Example 22.

Peeling strength and solder heat resistance were evaluated on theflexible copper clad laminate obtained in each of Examples 22 to 27 andComparative Examples 16 to 19 as described above. Water absorption ofeach adhesive sheet was evaluated as well. The results obtained areshown in Table 4.

TABLE 4 Peeling strength Peeling strength Peeling strength (kgf/cm)(kgf/cm) retention (%) after Solder Water (Before PCT treatment) (AfterPCT treatment) PCT treatment heat absorption 20° C. 150° C. 20° C. 150°C. 20° C. 150° C. resistance (%) Example 22 1.3 1.1 1.2 0.9 92 82 ◯ 0.4Example 23 1.3 1.1 1.2 0.9 92 82 ◯ 0.3 Example 24 1.5 1.2 1.4 1.0 93 83◯ 0.6 Example 25 1.4 1.2 1.3 1.0 93 83 ◯ 0.6 Example 26 1.3 1.1 1.2 1.092 91 ◯ 0.6 Example 27 1.3 1.1 1.2 1.0 92 91 ◯ 0.8 Comparative Example16 1.1 0.9 0.2 0.1 18 11 X 1.8 Comparative Example 17 0.3 0.2 0.0 0.0 00 ◯ 0.4 Comparative Example 18 1.3 0.2 0.2 0.0 15 0 ◯ 0.4 ComparativeExample 19 1.0 0.8 0.5 0.4 50 50 ◯ 0.5

Example 28

In a 1000 ml glass flask, 0.112 mole of 3,3′-bis(aminophenoxyphenyl)sulfone (hereinafter referred to as BAPS-M) wasadded to 263 g of dimethylformamide (DMF) and 0.112 mole of2,2-bis(4-hydroxyphenyl)propanebenzoate-3,3′,4,4′-tetracarboxylic aciddianhydride (hereinafter referred to as ESDA) was gradually added to thesolution to be stirred under a nitrogen atmosphere. The solution in theflask was further stirred in an ice-water bath for 30 minutes. When theviscosity reached 1500 poise, stirring was stopped and then a polyamicacid solution was obtained.

To this polyamic acid solution, 113 g of DMF, 26 g of β-picoline, and 45g of acetic anhydride were added. After stirring for 30 minutes,stirring was further continued below 100° C. for an hour forimidization. Then, this solution was added dropwise into methanol withvigorous stirring. The filamentous polyimide precipitated out of themethanol was pulverized by a mixer and then Soxhlet cleaning wasperformed with methanol. After drying at 110° C. for 2 hours, apolyimide powder was obtained.

20 g of the obtained polyimide powder, 5 g of Epikote 1032H60(manufactured by Shell International Chemicals Corporation), and 1.5 gof 4,4′-diaminodiphenyl sulfone (curing agent) were added to bedissolved in 102 g of THF by stirring. And then a polyimide adhesivesolution was obtained (solid content concentration: SC=20%).

Example 29

A polyimide adhesive solution (solid content concentration: SC=20%) wasobtained in the same manner as in Example 28 except that 1,4-dioxane wasused as an organic solvent instead of THF.

Example 30

A polyimide adhesive solution (solid content concentration: SC=20%) wasobtained in the same manner as in Example 28 except that dioxolan wasused as an organic solvent instead of THF.

Comparative Example 20

A polyimide adhesive solution (solid content concentration: SC=20%) wasobtained in the same manner as in Example 28 except thatdimethylformamide (DMF) was used as an organic solvent instead of THF.

Comparative Example 21

A polyimide adhesive solution (solid content concentration: SC=20%) wasobtained in the same manner as in Example 28 except thatN-methylpyrrolildone (NMP) was used as an organic solvent instead ofTHF.

Comparative Example 22

A polyimide adhesive solution (solid content concentration: SC=20%) wasobtained in the same manner as in Example 28 except thatdimethylacetoamide (DMAc) was used as an organic solvent instead of THF.

Comparative Example 23

The preparation of a polyimide adhesive solution was tried in the samemanner as in Example 28 except that methylethyl ketone (MEK) was used asan organic solvent instead of THF, but there were some insolubleportions.

Comparative Example 24

The preparation of a polyimide adhesive solution was tried in the samemanner as in Example 28 except that methanol was used as an organicsolvent instead of THF, but there were some insoluble portions.

Comparative Example 25

The preparation of a polyimide adhesive solution was tried in the samemanner as in Example 28 except that ethanol was used as an organicsolvent instead of THF, but there were some insoluble portions.

Example 28a, 28b, and 28c

The polyimide adhesive solution obtained in Example 28 was cast onto apolyimide film having a thickness of 25 μm (Apical 25AH, manufactured byKaneka Corporation). After drying by heating at 100° C. for 10 minutes,a film-state joining component having a thickness of 30 μm was obtainedby heating at 180° C. for 10 minutes in Example 28a, heating at 200° C.for 10 minutes in Example 28b, and heating at 220° C. for 10 minutes inExample 28c.

Examples 29a, 29b, and 29c

Film-state joining components in Examples 29a, 29b, and 29c wereobtained in the same manner as in Examples 28a through 29c except that apolyimide adhesive solution obtained in Example 29 was respectivelyused.

Examples 30a, 30b, and 30c Comparative Examples 20a, 20b, 20c, 21a, 21b,21c, 22a, 22b, and 22c

Film-state joining components were obtained in Examples 30a, 30b and30c, and Comparative Examples 20a, 20b, 20c, 21a, 21b, 21c, 22a, 22b,and 22c in the same manner and under the same conditions as in the aboveexamples. Joining components in a film state which were corresponding toComparative Examples 23, 24 and 25, wherein there were some insolubleportions, were not prepared.

Characteristic evaluation results of Examples 28 to 30 and ComparativeExamples 20 to 22 are shown in Table 5.

TABLE 5 THF Dioxane Dioxolan THF Dioxane Dioxolan Residual Example 28aExample 29a Example 30a Comparative Comparative Comparative Solvent 0.53.2 0.8 Example 20a Example 21a Example 22a Content (%) 5.1 8.0 6.2Example 28b Example 29b Example 30b Comparative Comparative Comparative0.0 1.3 0.2 Example 20b Example 21b Example 22b 2.0 4.3 3.5 Example 28cExample 29c Example 30c Comparative Comparative Comparative 0.0 0.2 0.1Example 20c Example 21c Example 22c 0.9 1.9 1.4 Peeling Example 28aExample 29a Example 30a Comparative Comparative Comparative Strength1.00 0.97 1.00 Example 20a Example 21a Example 22a (kgf/cm) 1.00 0.981.00 Example 28b Example 29b Example 30b Comparative ComparativeComparative 0.72 0.66 0.70 Example 20b Example 21b Example 22b 0.67 0.510.53 Example 28c Example 29c Example 30c Comparative ComparativeComparative 0.12 0.11 0.11 Example 20c Example 21c Example 22c 0.13 0.060.10

Example 31

In a 500 ml glass flask, 0.1487 mole of3,3′-bis(amino-phenoxyphenyl)sulfone (hereinafter referred to as BAPS-M)was added to 280 g of dimethylformamide (DMF). And then 0.1487 mole of2,2′-bis(4-hydroxyphenyl)propanedibenzoate 3,3′,4,4′-tetracarboxylicacid dianhydride (hereinafter referred to as ESDA) was gradually addedby heating at 130° C. under a nitrogen atmosphere with care to itsviscosity. When the viscosity reached 1500 poise, the addition of ESDAwas stopped and then a polyimide solution was obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued in a temperature atmosphere of 100° C. for an hourfor imidization. Then, this solution was added dropwise into methanolwith vigorous stirring. After drying filamentous polyimide precipitatedout of the methanol at 1000° C. for 30 minutes, the polyimide waspulverized by a mixer and then Soxhlet cleaning was performed withmethanol. After drying at 100° C. for 2 hours, a polyimide powder wasobtained. The transition temperature of the obtained polyimide was 140°C.

20 g of the obtained polyimide powder was dissolved in 83 g of DMF toobtain a varnish. The obtained varnish was cast onto a glass plate.After drying at 100° C. for 10 minutes, the varnish was peeled off fromthe glass plate and was set on a steel frame. A sheet having a thicknessof 25 μm was obtained by further drying at 150° C. for 30 minutes. Andthen, Epikote 1032H60 (manufactured by Shell International ChemicalsCorporation) was applied onto the surface of the obtained sheet so thatthe thickness may be 3 μm. After drying at 130° C. for 10 minutes, afilm-state joining c met was obtained. Its water absorption was 0.6%.The obtained film-state joining component was sandwiched between apolyimide film (Apical 25AH, manufactured by Kaneka Corporation) an,d acopper foil of 25 μm thickness, and then was heated at 200° C. andpressurized at pressure 3 MPa for 20 minutes to obtain a flexible copperclad laminate. Peeling strength and solder heat resistance were measuredon the obtained flexible copper clad laminate. Each measuring resultsare shown in Table 6.

TABLE 6 Peeling strength Water (kgf/cm) Solder heat absorption 20° C.150° C. resistance (%) Example 31 1.0 0.9 ◯ 0.6 Example 32 1.0 0.8 ◯ 0.5Example 33 1.0 0.8 ◯ 0.5 Example 34 1.1 0.7 ◯ 0.6 Comparative Example 260.1 0.1 ◯ 0.6 Comparative Example 27 0.9 0.2 X 2.0 Comparative Example28 1.0 0.9 X 1.8

Example 32

A polyimide powder was obtained in the same manner as in Example 31except that a diamine component was 4,4′-bis (aminophenoxyphenyl)propane. The obtained polyimide had a glass transition temperature of190° C. A film-state joining component was obtained in the same manneras in Example 31. And this material was measured for water absorption.By using this, a flexible copper clad laminate was obtained. Peelingstrength and solder heat resistance were measured on the obtainedflexible copper clad laminate. Each measuring results obtained are shownin Table 6.

Example 33

A polyimide powder was obtained in the same manner as in Example 31except that a diamine component was4,4′-[1,4-phenylenebis(1-methylethylidene). The obtained polyimide had aglass transition temperature of 210° C. A film-state joining componentwas obtained in the same manner as in Example 31. And this material wasmeasured for water absorption. By using this, a flexible copper cladlaminate was obtained. Peeling strength and solder heat resistance weremeasured on the obtained flexible copper clad laminate. Each measuringresults obtained are shown in Table 6.

Example 34

A film-state joining component was obtained in the same manner as inExample 31 except that the thermosetting resin content was TETRAD-C(manufactured by Mitsubishi Gas Chemical Co., Inc.). By using this, aflexible copper clad laminate was obtained. Peeling strength and solderheat resistance were measured on the obtained flexible copper cladlaminate. Each measuring results obtained are shown in Table 6.

Comparative Example 26

20 g of polyimide powder was dissolved in 83 g of DMF in the same manneras in Example 31. The obtained varnish was cast onto a glass plate.After drying at 100° C. for 10 minutes, the varnish was peeled off fromthe glass plate and was set on a steel frame. A sheet having a thicknessof 25 μm was obtained by further drying at 150° C. for 30 minutes. Theobtained sheet was sandwiched between a polyimide film (Apical 50AH,manufactured by Kaneka Corporation) and a copper foil of 25 μmthickness, and then was heated at 200° C. and pressurized at pressure 3MHa for 20 minutes to obtain a flexible copper clad laminate.

Comparative Example 27

20 g of Pratabond M1276 (Co-polymerized nylon, manufactured by NihonRilsan Co., Ltd.), 30 g of Epikote 1032H60, and 3 g of diaminodiphenylsulfone were dissolved in 83 g of DMF to obtain a varnish. The obtainedvarnish was cast onto a glass plate, dried at 100° C. for 10 minutes,peeled off from the glass plate and set on a steel frame. A polyimidesheet was obtained by further drying at 150° C. for 30 minutes. Thesheet obtained was measured for water absorption. The obtained sheet wassandwiched between a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness, and then was heatedat 200° C. and pressurized at pressure 3 MPa for 20 minutes to obtain aflexible copper clad laminate.

Comparative Example 28

A polyimide powder was obtained in the same manner as in Example 31except that ESDA was changed to benzophenone-tetracarboxylic aciddianhydride (BTDA). 20 g of the obtained polyimide powder was dissolvedin 83 g of DMF to obtain a varnish. The obtained varnish was cast onto aglass plate, dried at 100° C. for 10 minutes, peeled off from the glassplate and set on a steel frame. A sheet having a thickness of 25 μm wasobtained by further drying at 150° C. for 20 minutes. And then, Epikote1032H60 (manufactured by Shell International Chemicals Corporation) wasapplied onto the surface of the obtained sheet so that the thicknessafter drying may be 3 μm. After drying at 130° C. for 10 minutes, afilm-state joining component was obtained. The sheet obtained wasmeasured for water absorption. The obtained sheet was sandwiched betweena polyimide film (Apical 50AH, manufactured by Kaneka Corporation) and acopper foil of 25 μm thickness, and then was heated at 200° C. andpressurized at pressure 3 MPa for 20 minutes to obtain a flexible copperclad laminate.

Peeling strength and solder heat resistance were measured on theobtained flexible copper clad laminate. Each measuring results obtainedare shown in Table 6.

Example 35

In a 500 ml glass flask, 0.1487 mole of3,3′-bis(amino-phenoxyphenyl)sulfone (hereinafter referred to as BAPS-M)was added to 280 g of dimethylformamide (DMF). And then 0.1487 mole of2,2′-bis (4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylicacid dianhydride (hereinafter referred to as ESDA) was gradually addedwhile heating at 130° C. under a nitrogen atmosphere with care to itsviscosity. When the viscosity reached 1500 poise, the addition of ESDAwas stopped and then a polyimide solution was obtained.

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued in a temperature atmosphere of 100° C. for an hourfor imidization. Then, this solution was added dropwise into methanolwith vigorous stirring. After drying filamentous polyimide precipitatedout of the methanol at 100° C. for 30 minutes, the polyimide waspulverized by a mixer and then Soxhlet cleaning was performed withmethanol. After drying at 100° C. for 2 hours, a polyimide powder wasobtained. The obtained polyimide had a glass transition temperature of140° C. The water absorption was 0.6.

20 g of the obtained polyimide powder, 5 g of Epikote 1032H60(manufactured by Shell International Chemicals Corporation), and 3 g of4,4′-diaminodiphenyl sulfone were dissolved in 83 g of DMF to obtain avarnish. The obtained varnish was cast onto a polyimide film having athickness of 25 μm (Apical 25AH manufactured by Kaneka Corporation).After drying at 100° C. for 10 minutes, the varnish was further dried at150° C. for 10 minutes to obtain a film-state joining component having athickness of 30 μm.

The obtained film-state joining component was sandwiched between apolyimide film (Apical 50AH, manufactured by Kaneka Corporation) and acopper foil of 25 μm thickness, and then was heated at 200° C. andpressurized at pressure 3 MPa for 20 minutes to obtain a flexible copperclad laminate. Peeling strength and solder heat resistance were measuredon the obtained flexible copper clad laminate. Each measuring resultsobtained are shown in Table 7.

TABLE 7 Peeling strength Water (kgf/cm) Solder heat absorption 20° C.150° C. resistance (%) Example 36 1.0 0.9 ◯ 0.6 Example 37 1.0 0.8 ◯ 0.5Example 38 1.1 0.9 ◯ 0.5 Example 39 1.2 0.7 ◯ 0.7 Comparative Example 291.0 0.9 X 1.8 Comparative Example 30 0.2 0.1 ◯ 0.6 Comparative Example31 1.0 0.2 X 2.0

Example 36

A polyimide powder was obtained in the same manner as in Example 35except that a diamine component was 4,4′-bis(aminophenoxyphenyl)propane. The obtained polyimide had a glasstransition temperature of 190° C. Its water absorption was 0.5. Afilm-state joining component was obtained in the same manner as inExample 35. Further, a flexible copper clad laminate was obtained in thesame manner as in Example 35. Peeling strength and solder heatresistance were measured on the obtained flexible copper clad laminate.Each measuring results obtained are shown in Table 7.

Example 37

A polyimide powder was obtained in the same manner as in Example 35except that a diamine component was4,4′-[1,4-phenylenebis(1-methylethylidene). The obtained polyimide had aglass transition temperature of 210° C. Its water absorption was 0.5. Afilm-state joining component was obtained in the same manner as inExample 35 . Further, a flexible copper clad laminate was obtained inthe same manner as in Example 35. Peeling strength and solder heatresistance were measured on the obtained flexible copper clad laminate.Each measuring results obtained are shown in Table 7.

Example 38

A film-state joining component and a flexible copper clad laminate wereobtained in the same manner as in Example 35 except that an adhesive wasadded to 20 g of polyimide powder, 5 g of glycidylamine-type epoxyresin; TETRAD-C (manufactured by Mitsubishi Gas Chemical Co., Inc.), 3 gof 4,4′-diaminophenyl sulfone to be dissolved in 83 g of DMF. Peelingstrength and solder heat resistance were measured on the obtainedflexible copper clad laminate. Each measuring results obtained are shownin Table 7.

Comparative Example 29

A polyimide powder was obtained ion the same manner as in Example 35except that ESDA was changed to benzophenone-tetracarboxylic aciddianhydride. 20 g of the obtained polyimide powder, 5 g of Epikote1032H60 (manufactured by Shell International Chemicals Corporation), and0.5 g of 4,4′-diaminophenyl sulfone were dissolved in 83 g of DMF toobtain a varnish. The obtained varnish was cast onto a polyimide film(Apical 25AH, manufactured by Kaneka Corporation). After drying at 100°C. for 10 minutes, the varnish was further dried at 150° C. for 10minutes to obtain a film-state joining component having a thickness of30 μm. The obtained joining component was sandwiched between a polyimidefilm (Apical 50AH, manufactured by Kaneka Corporation) and a copper foilof 25 μm thickness, and then was heated at 2000° C. and pressurized atpressure 3 MPa for 20 minutes to obtain a flexible copper clad laminate.

Comparative Example 30

20 g of the polyimide powder obtained in Example 35 was dissolved in 83g of DMF to obtain a varnish. The obtained varnish was cast onto apolyimide film (Apical 25AH, manufactured by Kaneka Corporation). Afterdrying at 100° C. for 10 minutes, the varnish was further dried at 150°C. for 10 minutes to obtain a film-state joining component having athickness of 30 μm. The obtained joining component was sandwichedbetween a polyimide film (Apical 50AH, manufactured by KanekaCorporation) and a copper foil of 25 μm thickness. After heating at 200°C. and applying a pressure of 3 MPa for 20 minutes, a flexible copperclad laminate was obtained.

Comparative Example 31

20 g of Pratabond M1276 (Co-polymerized nylon, manufactured by NihonRilsan Co., Ltd.e), 5 g of Epikote 1032H60, and 3 g of4,4′-diaminodiphenyl sulfone were dissolved in 83 g of DMF to obtain avarnish. The obtained varnish was cast onto a polyimide film (Apical25AH, manufactured by Kaneka Corporation), dried at 100° C. for 10minutes, further dried at 150° C. for 10 minutes. A film-state joiningcomponent having a thickness of 30 μm was obtained. The obtained joiningcomponent was sandwiched between a polyimide film (Apical 50AH,manufactured by Kaneka Corporation) and a copper foil of 25 μmthickness, and then was heated at 200° C. and pressurized at pressure 3MPa for 20 minutes to obtain a flexible copper clad laminate.

Peeling strength and solder heat resistance were measured on theflexible copper clad laminate obtained in Comparative Examples 29 to 31.The results obtained are shown in Table 7.

Example 39

In a 500-ml glass flask, 0.1487 mole of 3,3′-bis (amino-phenoxyphenyl)sulfone (hereinafter referred to as BAPS-M) was added to 280 g ofdimethylformamide (IMF). And then 0.1487 mole of2,2′-bis(4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylicacid dianhydride (hereinafter referred to as ESDA) was gradually addedwhile heating at 130° C. under a nitrogen atmosphere, having paidattention to the viscosity. When the viscosity reached 1500 poise, theaddition of ESDA was stopped and then a polyimide solution was obtained.The viscosity was measured by a B-type viscometer (manufactured by TokyoKeiki Co., Ltd.).

To this polyamic acid solution, 150 g of DMF, 35 g of β-picoline, and 60g of acetic anhydride were added. After stirring for an hour, stirringwas further continued below 100° C. for an hour for imidization. Then,this solution was added dropwise into methanol with vigorous stirring.After drying filamentous polyimide precipitated out of the methanol at100° C. for 30 minutes, the polyimide was pulverized by a mixer and thenSoxhlet cleaning was performed with methanol. After drying at 100° C.for 2 hours, a polyimide powder was obtained.

20 g of the obtained polyimide powder, 5 g of Epikote 1032H60(manufactured by Shell International Chemicals Corporation), and 3 g of4,4′-diaminodiphenyl sulfone were dissolved in 83 g of DMF to obtain avarnish. The obtained varnish was cast onto a PET film, dried at 100° C.for 10 minutes, peeled off the PET film and set on a metal support. Afilm which comprises a thermoplastic polyimide and a thermosetting resinused as an adhesive layer in the present invention was obtained bydrying at 150° C. for 20 minutes.

The obtained sheet was laminated on a polyimide film (Apical 50AH,manufactured by Kaneka Corporation) and a sheet of released paper inorder to be laminated at the temperature of 150° C. and at the speed of2.2 cm/min to obtain a desired adhesive laminated film for wire rodcoating.

The obtained thermoplastic polyimide had a glass transition temperatureof 140° C. Its water absorbtion was 0.9%. Its dielectric constant was2.95.

As a reference to the obtained adhesive laminate film for wire rodcoating and the adhesion strength of the wire rod, the released paper ofthis laminate film was peeled off to dispose a copper foil. Aftercrimping at 180° C. under a pressure of 30 kg/cm² for 10 minutes,peeling strength was measured to be 1.1 kgf/cm. When a radiationresistance test was performed on the obtained adhesive laminate film forwe rod coating, any changes, such as discoloration and deterioration didnot occur on the film. The results obtained are shown in Table 8. Theradiation resistance test was performed by 5 MGy irradiation using anelectron beam of 2 MeV.

TABLE 8 Glass Water Dielectric Peeling Radiation transition absorptionconstant strength resistance tempertaure (° C.) (%) (—) (kgf/cm) testExample 39 140 0.9 2.95 1.1 ; Example 40 190 0.8 2.90 1.1 ; Example 41210 0.8 2.88 1.1 ; Example 42 140 0.9 2.96 1.2 ; Comparative Example 32None 2.6 3.50 Unattached ; Comparative Example 33 178 2.0 3.80 0.3Blackened

Example 40

A polyamic acid was obtained in the same manner as in Example 39 exceptthat a diamine component was 4,4′-bis (aminophenoxyphenyl)propane. Thispolyamic acid was applied by flow casting onto a polyimide film (Apical(Trade mark) manufactured by Kaneka Corporation) used in Example 39.After heating at 80° C. for 25 minutes, an adhesive laminate film forwire rod coating was obtained by heating the polyamic acid at 150° C.,250° C., 270° C., and 300° C. respectively for 5 minutes to be imidized.

When the obtained film was measured for each characteristic in the samemanner as in Example 39, the polyimide resin layer had a glasstransition temperature of 190° C., its water absorption was 0.8%, anddielectric constant was 2.90. When peeling strength was measured in thesame manner as in Example 39, its peeling strength was 1.1 kgf/cm. Whena radiation resistance test was performed on the obtained adhesivelaminate film for wire rod coating, any changes, such as, discolorationand deterioration did not occur on the film. The results obtained areshown in Table 8.

Example 41

A polyamic acid was obtained in the same manner as in Example 39 exceptthat a diamine component was4,4′-[1,4-phenylenebis(1-methylethylidene)bisaniline. This polyamic acidwas applied by flow casting onto the polyimide film (Apical (Trade mark)manufactured by Kaneka Corporation) used in Example 39. After heating at80° C. for 25 minutes, an adhesive laminate film for wire rod coatingwas obtained by heating the polyamic acid at 150° C., 250° C., 270° C.,and 300° C. respectively for 5 minutes to be imidized.

When the obtained film was measured for each characteristic in the samemanner as in Example 39, the polyimide resin layer had a glasstransition temperature of 210° C., its water absorption was 0.8%, anddielectric constant was 12.88. When peeling strength was measured in thesame manner as in Example 39, its peeling strength was 1.1 kgf/cm. Whena radiation resistance test was performed on the obtained adhesivelaminate film for wire rod coating, any changes, such as discolorationand deterioration did not occur on the film. The results obtained areshown in Table 8.

Example 42

An adhesive laminate film for wire rod coating consisting essentially ofa thermoplastic polyimide and a thermosetting resin was obtained in thesame manner as in Example 39 except that a thermosetting component wasTETRAD-C (manufactured by Mitsubishi Gas Chemical Co., Inc.).

When the obtained film was measured for each characteristic in the samemanner as in Example 39, the polyimide resin layer had a glasstransition temperature of 140° C., its water absorption was 0.9%, anddielectric constant was 2.96. When peeling strength was measured in thesame manner as in Example 39, its peeling strength was 1.2 kgf/cm. Whena radiation resistance test was performed on the obtained adhesivelaminate film for wire rod coating, any changes, such as discolorationand deterioration, did not occur on the film. The results obtained areshown in Table 8.

Comparative Example 32

A polyamic acid was obtained from pimellitic acid dianhydride and ODA(oxydianiline) substantially in the same manner as in Example 39. Thispolyamic acid was applied by flaw casting onto the polyimide film(Apical (Trade mark) manufactured by Kaneka Corporation) used in Example39. After heating at 80° C. for 25 minutes, an adhesive laminate filmfor wire rod coating was obtained by heating the polyamic acid at 150°C., 250° C., 270° C., and 300° C. respectively for 5 minutes to beimidized.

When the obtained film was measured for each characteristic in the samemanner as in Example 39, the polyimide resin layer had no glasstransition temperature, its water absorption was 2.6%, and dielectricconstant was 3.5. It was impossible to measure peeling strength of theobtained adhesive laminate film for wire rod coating under theconditions of temperature at 180° C. under a pressure of 30 kg/cm² for10 minutes due to being incapable to be bonded. When a radiationresistance test was performed on the obtained adhesive laminate film forwire rod coating, any changes, such as discoloration and deterioration,did not occur on the film. The results obtained are shown in Table 8.

Comparative Example 33

An adhesive laminate film for wire rod coating was obtained in the samemanner as in Example 40 except that an adhesive which comprised Epikote828 (Trade mark: manufactured by Shell International ChemicalsCorporation) was used instead of a polyimide film having thermoplasticproperties (adhesion).

When the obtained film was measured for respective characteristics inthe same manner as in Example 39, the adhesive layer had a glasstransition temperature of 178° C., its water absorption was 2.0%, anddielectric constant was 3.8. The peeling strength of the obtainedadhesive laminate film for wire rod coating was 0.3 kg/cm. As a resultof a radiation resistance test, the film was blackened. The resultsobtained are shown in Table 8.

Industrial Applicability

The present invention can provide a polyimide resin of novelconfiguration having excellent adhesion and low water absorption, aswell as excellent heat resistance, mechanical strength, and electricalcharacteristics which are found in polyimide.

In addition, the present invention can provide a resin composition whichis capable of being used as an adhesive at relatively low temperatures,for example, 250° C. Unlike conventional heat-resisting adhesives, theresin composition of the present invention is not necessary to be usedat high temperatures, but it has excellent adhesive strength on apolyimide film, which retains excellent adhesive strength up to hightemperatures. Tie resin composition can achieve a low water absorptionas low as 1.5% or lower. Since its peeling strength retention is highafter a PCT treatment due to control of the residual volatile componentof 3 wt % or lower, it has solder heat resistance free from swelling andthe like when it is dip-soldered. Further, the polyimide resincomposition is capable of controlling immersion of a solvent andmaintaining high retention of peeling strength after the PCT treatmentwhich is a reliability test of materials for electronic devices becausean amino-terminated polyimide oligomer used as a polyimide resin hasmultiple cross-liking points with epoxy resin to be close packedstructure.

Moreover, the present invention can provide an adhesive solution whichis capable of removing its solvent by drying at relatively lowtemperatures, using the polyimide resin of the present invention and aspecific solvent, which lead to powerful adhesive strength on alaminated layer to be formed later.

As described above, the polyimide resin, resin composition, and adhesivesolution have an advantage of having great technical value as materialsfor electronic devices required for high reliability and heatresistance.

The adhesive laminate film for wire rod coating according to the presentinvention is constructed by a polyimide having excellent heatresistance, radiation resistance, electrical characteristics, chemicalresistance, and low temperature characteristics, and an adhesive layerwhich comprises a thermoplastic resin having a glass transitiontemperature of 100 to 250° C., water absorption of 1.5% or lower,dielectric constant of 3.2 or lower, and a thermosetting resin havingexhibiting excellent adhesion at low temperatures. The adhesive laminatefilm for wire rod coating has, therefore, excellent characteristicscomprehensively, such as superior workability, flexibility, and adhesionat low temperatures, few deterioration caused by water adsorption, fewdielectric loss at the time of passage of electric current and superiorradiation resistance when coating the film on a wire rod. The adhesivelaminate film is particularly suitable for coating on a superconductivewire rod, and the like, so that the film is most suitable for a use fora superconductive magnet for accelerator. Specifically, when theadhesive laminate film for wire rod coating according to the presentinvention is coated on a wire rod, the film can be bonded to the wirerod by heating within the scope of temperatures at which littledeterioration in characteristics of the wire rod, so that the coating ofthe film is possible without any loss of characteristics of the wire rodcoated with the film, for example, superconductivity characteristicswhen the wire rod is a superconductive wire rod.

There have thus been shown and described a novel polyimide resin, aresin composition, an adhesive solution, a film-state joining component,an adhesive laminate film and a production method therefor which fulfillall the objects and advantages sought therefor. Many changes,modifications, variations and other uses and applications of the subjectinvention will, however, become apparent to those killed in the artafter considering this specification and the accompanying drawings whichdisclose the preferred embodiments thereof. All such changes,modifications, variations and other uses and applications which do notdepart from the spirit and scope of the invention, which is to belimited only by the claims which follow.

What is claimed is:
 1. A resin composition comprising a polyimide resinobtained by reacting tetracarboxylic acid dianhydride containing esteracid dianhydride represented by the general formula (1):

wherein X represents —(CH₂)_(k)—, or is a divalent group comprising anaromatic ring; and k is an integer from 1 to 10; with diamine containingan aromatic diamine represented by the general formula (2):

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group; and n is an integer from 0 to 4, R₁ whose number is n isthe same or different, and/or an aromatic diamine represented by thegeneral formula (3):

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)n—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—, R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group, and are the same ordifferent groups; x, y, z, m, and n are each an integer from 0 to 4; andA whose number is (m+1) is respectively the same or different; and athermosetting resin.
 2. A resin composition comprising a polyimide resinobtained by reacting tetracarboxylic acid dianhydride containing esteracid dianhydride represented by the general formula (1):

wherein X represents —(CH₂)_(k)— or is a divalent group comprising anaromatic ring; and k is an integer from 1 to 10; with aromatic diaminerepresented by the general formula (4):

wherein Y is at least one selected from the groups consisting of asingle bond, —CO—, —SO₂—, —O—, —S—, —C(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—; p and q are each an integer from 1 to 5; and athermosetting resin.
 3. A polyimide resin obtained by reactingtetracarboxylic acid dianhydride containing ester-acid dianhydriderepresented by the general formula (1):

wherein X represents —(CH₂)_(k)— or is a divalent group comprising anaromatic ring; and k is an integer from 1 to 10; with aromatic diaminerepresented by the general formula (4):

wherein Y is at least one selected from the groups consisting of asingle bond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—; p and q are each an integer from 1 to 5, andsiloxane diamine represented by the general formula (5):

wherein R₅ and R₆ are each a divalent aliphatic group whose carbonnumber is from 1 to 4 or a divalent aromatic group; R₇, R₈, R₉, and R₁₀are each a monovalent aliphatic group whose carbon number is from 1 to 4or a monovalent aromatic group; and n is an integer from 1 to
 10. 4. Theresin composition according to claim 2, wherein said diamine representedby the general formula (4) is aromatic diamine represented by thegeneral formula (6):

wherein Y is at least one group selected from the groups consisting of asingle bond -, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—; p and q are each an integer from 1 to
 5. 5. Thepolyimide resin according to claim 3, further comprising siloxanediamine in an amount of 1 to 30 mole % based on the total amount ofdiamine.
 6. A resin composition comprising a polyimide resin obtained byreacting tetracarboxylic acid dianhydride containing2,2-(4-hydroxyphenyl) propanedibenzoate-3,3′,4,4′-tetracarboxylic aciddianhydride represented by the general formula (7),

aromatic diamine represented by the formula (2),

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group; n is an integer from 0 to 4; and R₁ whose number is n isthe same or different: and/or diamine containing aromatic diaminerepresented by the general formula (3):

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—, R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group, and are the same ordifferent groups; X, y, z, m, and n are each an integer from 0 to 4; andA whose number is (m+1) is respectively the same or different; and athermosetting resin.
 7. A resin composition comprising a polyimide resinobtained by reacting tetracarboxylic acid dianhydride containingester-acid dianhydride represented by the general formula (1):

wherein X represents —(CH₂)_(k)— or is a divalent group comprising anaromatic ring; and k is an integer from 1 to 10; with aromatic diaminerepresented by the general formula (4):

wherein Y is at least one selected from the groups consisting of asingle bond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂, or —C(═O)O—; p and q are each an integer from 1 to 5, andsiloxane diamine represented by the general formula (5):

wherein R₅ and R₆ are each a divalent aliphatic group whose carbonnumber is from 1 to 4 or a divalent aromatic group; R₇, R₈, R₉, and R₁₀are each a monovalent aliphatic group whose carbon number is from 1 to 4or a monovalent aromatic group; and n is an integer from 1 to 10; and athermosetting resin.
 8. The resin composition according to any one ofclaims 1, 2, 6, or 7, wherein the polyimide resin has a glass transitiontemperature from 100° C. to 250° C. and water absorption of 1.5% orlower.
 9. The resin composition according to claim 8, wherein thepolyimide resin lies a glass transition temperature from 100° C. to 250°C., water absorption of 1.5% or lower, and dielectric constant of 3.2 orlower.
 10. A polyimide adhesive solution in which said polyimide resinreacting tetracarboxylic acid dianhydride containing 50 mole % or moreof an ester acid dianhydride represented by the general formula (1):

wherein X represents —(CH₂)_(k)—, or is a divalent group comprising anaromatic ring; and k is an integer from 1 to 10; with diamine containingan aromatic diamine represented by the general formula (2):

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group; and n is an integer from 0 to 4, R₁ whose number is n isthe same or different, and/or an aromatic diamine represented by thegeneral formula (3) or (4):

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—, R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group, and are the same ordifferent groups; x, y, z, m, and n are each an integer from 0 to 4; andA whose number is (m+1) is respectively the same or different, Y is atleast one selected from the groups consisting of a single bond, —CO—,—SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—, —C(CF₃)₂—, or —C(═O)O—;p and q are each an integer from 1 to 5, and siloxane diaminerepresented by the general formula (5):

wherein R₅ and R₆ are each a divalent aliphatic group whose carbonnumber is from 1 to 4 or a divalent aromatic group; R₇, R₈, R₉, and R₁₀are each a monovalent aliphatic group whose carbon number is from 1 to 4or a monovalent aromatic group; and n is an integer from 1 to 10; epoxyresin, and a curing agent are dissolved in an organic solvent.
 11. Afilm-like joining component formed by laminating a thermosetting resinonto one side of both sides of a base film comprising a thermoplasticpolyimide resin selected from the group consisting of; a polyimide resinobtained by reacting tetracarboxylic acid dianhydride containing esteracid dianhydride represented by the general formula (1):

wherein X represents —(CH₂)_(k)—, or is a divalent group comprising anaromatic ring; and k is an integer from 1 to 10; with diamine containingan, aromatic diamine represented by the general formula (2):

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group; and n is an integer from 0 to 4, R₁ whose number is n isthe same or different, and/or an aromatic diamine represented by thegeneral formula (3):

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—, R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group, and are the same ordifferent groups; x, y, z, m, and n are: each an integer from 0 to 4;and A whose number is (m+1) is respectively the same or different; apolyimide resin obtained by reacting tetracarboxylic acid dianhydridecontaining ester acid dianhydride represented by the general formula(1):

wherein X represents —(CH₂)_(k)— or is a divalent group comprising anaromatic ring; and k is n integer from 1 to 10; with aromatic diaminerepresented by the general formula (4):

wherein Y is at least one selected from the groups consisting of asingle bond, —CO—, —SO₂—, —O—, —S—, —C(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—; p and q are each an integer from 1 to 5; apolyimide resin obtained by reacting tetracarboxylic acid dianhydridecontaining ester-acid dianhydride represented by the general formula(1):

wherein X represents —(CH₂)_(k)— or is a divalent group comprising anaromatic ring; and k is an integer from 1 to 10; with aromatic diaminerepresented by the general formula (4):

wherein Y is at least one selected from the groups consisting of asingle bond, —CO—, —SO₂—, —O—, —S—, —(CH₂)_(q)—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, or —C(═O)O—; p and q are each an integer from 1 to 5, andsiloxane diamine represented by the general formula (5):

wherein R₅ and R₆ are each a divalent aliphatic group whose carbonnumber is from 1 to 4 or a divalent aromatic group; R₇, R₈, R₉, and R₁₀are each a monovalent aliphatic group whose carbon number is from 1 to 4or a monovalent aromatic group; and n is an integer from 1 to 10; apolyimide resin obtained by reacting tetracarboxylic acid dianhydridecontaining 2,2-(4-hydroxyphenyl)propanedibenzoate-3,3′,4,4′-tetracarboxylic acid dianhydride representedby the general formula (7),

with aromatic diamine represented by the formula (2),

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen group; n is an integer from 0 to 4; and R₁ whose number is n isthe same or different; and/or diamine containing aromatic diaminerepresented by the general formula (3):

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O—, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S—, or —SO₂—, R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group, and are the same ordifferent groups; X, y, z, m, and n are each an integer from 0 to 4; andA whose number is (m+1) is respectively the same or different; and apolyimide resin obtained by reacting tetracarboxylic acid dianhydridewhich is adjusted to have a residual impurities content of 1 wt % orlower and contains 2,2-(4-hydroxyphenyl)propanedibenzoate-3,3′4,4′-tetracarboxylic acid dianhydride representedby the general formula (7),

with aromatic diamine represented by the general formula (2),

wherein R₁ represents alkyl, fluoro-alkyl, and alkoxyl groups or ahalogen groups; n is an integer from 0 to 4, and R₁ whose number is n isthe same or different; and/or diamine containing aromatic diaminerepresented by the general formula (3),

wherein A is at least one selected from the groups consisting of asingle bond, —O—, —(CH₂)_(n)—, —CO—, —C(═O)O, —NHCO—, —C(CH₃)₂—,—C(CF₃)₂—, —S— or —SO₂—, R₂, R₃, and R₄ represent independently alkyl,fluoro-alkyl, and alkoxyl groups or a halogen group; and are the same ordifferent groups; X, y, z, m, and n are each an integer from 0 to 4; andA whose number is (m+1) is respectively the same or different.
 12. Theresin composition according to any one of claims 1, 2, 6, or 7, whereinsaid thermosetting resin is an epoxy resin.
 13. The resin compositionaccording to claim 12, wherein said thermosetting resin includes twoepoxy groups or more.
 14. The resin composition according to claim 12,wherein said epoxy resin has an epoxy equivalent of 250 or less.
 15. Theresin composition according to any one of claims 1, 2, 6, or 7, havingwater absorption after curing of 1.5% or lower.
 16. The resincomposition according to claim 12, comprising said polyimide resin andsaid epoxy resin, wherein the resin composition has a residual volatilecomponent after curing of 3 wt % or lower.
 17. The resin compositionaccording to claim 16, wherein components of said residual volatilecomponent are at least one kind of solvent having a low boiling pointwhich dissolves said polyimide resin and said epoxy resin.
 18. The resincomposition according to claim 12, wherein said polyimide resin isamine-terminated polyimide oligomer.
 19. The resin composition accordingto claim 18, wherein said polyimide oligomer has a number-averagemolecular weight of 2,000 to 50,000.
 20. The polyimide adhesive solutionaccording to claim 10, wherein said organic solvent contains a cyclicether solvent of 30 wt % or higher.
 21. A film-like joining componentaccording to claim 11, wherein said thermosetting resin has a filmthickness after dried of 0.5 to 5 μm.
 22. A film-like joining componentobtained by laminating the resin composition according to claim 12 onone side or both sides of a polyimide base film.
 23. A film-like joiningcomponent obtained by depositing a film-like resin composition layer ona polyimide base film, wherein said film-like resin composition isobtained by dissolving the resin composition according to claim 12 in anorganic solvent, applying by flow or casting onto a support, and peelingoff a coating film of the resin composition from the support.
 24. Afilm-like joining component having a film-like resin composition layer,wherein said film-like resin is obtained by dissolving the resincomposition according to claim 12 in an organic solvent, applying byflow or casting onto at least one side of a polyimide base film, anddrying.
 25. A film-like joining component obtained by applying thepolyimide adhesive solution according to claim 10 by flow or castingonto a support and peeling off an adhesive coating film from thesupport.
 26. A film-like joining component having a polyimide adhesivelayer on its surface, wherein said polyimide adhesive layer, is obtainedby applying the polyimide adhesive solution according to claim 10 byflow or casting onto at least one side of a polyimide base film, anddrying.
 27. An adhesive laminate film for wire rod coating using thefilm-like joining component according to claim 22.